Autosport Labs - User contributions [en]

MJLJ V3 vehicle installation guide

2008-02-25T00:18:42Z

Alexander: /* Tachometers that require a high-voltage kickback pulse */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Existing Vacuum Advance vacuum port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole, which is actually covered by the edge of the throttle plate at idle. That is called Ported Vacuum. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

You can test whether you have ported vacuum or not: pull the vac hose off the vacuum advance unit. With your finger over the end of the hose, you should feel vacuum with the engine revved above idle. Assuming yes, let the engine speed drop back to idle. Is there still vacuum? If not (most likely), that means you have ported vacuum, and should find another source of vacuum, somewhere on the manfold.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil from which to detect this pulse. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternative approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

====Smiths RVI type tachometers====

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

MJLJ V3 vehicle installation guide

2008-02-25T00:18:16Z

Alexander: /* Tachometers that require a high-voltage kickback pulse */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Existing Vacuum Advance vacuum port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole, which is actually covered by the edge of the throttle plate at idle. That is called Ported Vacuum. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

You can test whether you have ported vacuum or not: pull the vac hose off the vacuum advance unit. With your finger over the end of the hose, you should feel vacuum with the engine revved above idle. Assuming yes, let the engine speed drop back to idle. Is there still vacuum? If not (most likely), that means you have ported vacuum, and should find another source of vacuum, somewhere on the manfold.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil, from which to detect this pulse. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternative approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

====Smiths RVI type tachometers====

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

MJLJ V3 vehicle installation guide

2008-02-25T00:17:13Z

Alexander: /* Existing Vacuum Advance vacuum port */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Existing Vacuum Advance vacuum port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole, which is actually covered by the edge of the throttle plate at idle. That is called Ported Vacuum. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

You can test whether you have ported vacuum or not: pull the vac hose off the vacuum advance unit. With your finger over the end of the hose, you should feel vacuum with the engine revved above idle. Assuming yes, let the engine speed drop back to idle. Is there still vacuum? If not (most likely), that means you have ported vacuum, and should find another source of vacuum, somewhere on the manfold.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil to detect this pulse from. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternative approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

====Smiths RVI type tachometers====

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

MJLJ V3 vehicle installation guide

2008-02-25T00:16:06Z

Alexander: /* Existing Vacuum Advance vacuum port */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Existing Vacuum Advance vacuum port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole, which is actually covered by the edge of the throttle plate at idle. That is called Ported Vacuum. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

You can test whether you have ported vacuum or not: pull the vac hose off the vacuum advance unit. With your finger over the end of the hose, you should feel vacuum with the engine revved above idle. Assuming yes, let the engine speed drop back to idle. Is there still vacuum? If not (most likely), that means you have ported vacuum, and should find another source of vacuum somewhere on the manfold.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil to detect this pulse from. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternative approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

====Smiths RVI type tachometers====

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

MJLJ V3 vehicle installation guide

2008-02-25T00:15:27Z

Alexander: /* Using existing Vacuum Advance port */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Existing Vacuum Advance vacuum port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole which is actually covered by the edge of the throttle plate, at idle. That is called Ported Vacuum. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

You can test whether you have ported vacuum or not: pull the vac hose off the vacuum advance unit. With your finger over the end of the hose, you should feel vacuum with the engine revved above idle. Assuming yes, let the engine speed drop back to idle. Is there still vacuum? If not (most likely), that means you have ported vacuum, and should find another source of vacuum somewhere on the manfold.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil to detect this pulse from. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternative approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

====Smiths RVI type tachometers====

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

MJLJ V3 vehicle installation guide

2008-02-25T00:14:37Z

Alexander: /* Using existing Vacuum Advance port */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Using existing Vacuum Advance port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole which is actually covered by the edge of the throttle plate, at idle. That is called Ported Vacuum. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

You can test whether you have ported vacuum or not: pull the vac hose off the vacuum advance unit. With your finger over the end of the hose, you should feel vacuum with the engine revved above idle. Assuming yes, let the engine speed drop back to idle. Is there still vacuum? If not (most likely), that means you have ported vacuum, and should find another source of vacuum somewhere on the manfold.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil to detect this pulse from. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternative approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

====Smiths RVI type tachometers====

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

MJLJ V3 vehicle installation guide

2008-02-24T22:39:21Z

Alexander: /* Using EDIS PIP signal */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Using existing Vacuum Advance port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole which is actually covered by the edge of the throttle plate, at idle. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil to detect this pulse from. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternative approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

====Smiths RVI type tachometers====

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

MJLJ V3 vehicle installation guide

2008-02-24T22:32:03Z

Alexander: /* Using EDIS PIP signal */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Using existing Vacuum Advance port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole which is actually covered by the edge of the throttle plate, at idle. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil to detect this pulse from. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternate approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

====Smiths RVI type tachometers====

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

Troubleshooting the MegaJolt Lite Jr.

2008-02-24T22:24:23Z

Alexander: /* Communication stops when engine is running */

==Configuration software compatibility==

If you see an error message while attempting to communicate with the MJLJ, such as 'Could not open port' or 'Timeout reading runtime data' you can use a terminal program to directly test the MJLJ unit.

Here are the instructions for this testing procedure, using the common 'Hyperterminal' software.

===Troubleshooting with Hyperterminal===

Open up Hyperterminal. create a connection, and configure it to connect directly to the COM port you are using for the MJLJ.

When it asks for the communication settings, use the following:

Bits Per Second: 4800
Data Bits: 8
Parity: None
Stop Bits: 1
Flow Control: none

When you get to the main screen, send a capital 'C' to the controller. you won't see what you type echoed on the screen, but the controller should 'reply' with what looks like a sequence of random data. This simulates the Configuration software requesting the controller's current configuration

Pressing 'S' returns the current runtime status; You will see only a few characters displayed.

If the above does not work, or if Hyperterminal indicates a COM port or communications error:

#Use a different serial cable. The cable you're using might not be compatible serial cable, or may have a broken internal connection.
#Are you using the same serial port with other applications? Programs like synchronization software for hand-held devices like the Palm are known for keeping the serial port open, preventing other applications from accessing it.
#As a debugging step, try a different computer. This will at least let you know the MJLJ and software can communicate, and will help narrow down the source of the problem.
#If you're using a USB-serial adapter, make sure the latest drivers are installed, the driver shows no errors, and you know which COM port it was installed on. Often the USB-Serial adapter will install on a high COM port number, like COM6. You can verify this by accessing 'Device Manager' in Windows and viewing the properties of the USB-Serial adapter under 'Ports'.

If you can get the expected response from the MJLJ, then there is a configuration problem with the MJLJ software. Verify you have the correct COM port set under 'Options'. If the trouble persists, check for a newer version of the software, or inquire on the forums[http://www.autosportlabs.org] for additional help.

==Hardware Troubleshooting==
If you built the MJLJ from a kit and your controller does not communicate or otherwise doesn't seem to be 'alive', perform the following checks;

===Check Power===
*Verify you have an adequate power supply, correctly connected to the MJLJ unit. See the [[MJLJ_V3_vehicle_installation_guide|Vehicle installation guide]]
*With the unit powered up, check to make sure the correct voltage (+5v) is present at all of the power input pins of the integrated circuits and oscillator.

===Ensure sure the components are installed correctly===
*Diodes and capacitors installed with the correct polarity (capacitors marked with a '+' or '-' sign)
*Integrated circuits, oscillator and transistors with the correct polarity (orient the notch on the chip with the notch shown on the circuit board)
===Check for good solder joints===
*Carefully inspect the pins to make sure the solder connections are bright and flow completely around the pins and onto the pad.
*Ensure that you haven't accidentally lifted the pad away from the board and broken a solder trace.
*Check for solder 'bridges' where you might have solder across two pads, resulting in a short circuit.

==MJLJ communicates with Configuration software; No RPM signal==

If you can communicate with the MJLJ software but cannot get an RPM signal from the EDIS module-

#Check the connection between the EDIS module and the MJLJ. Ensure the PIP signal from the EDIS module is connected to the correct pin on the Molex connector. Review the MJLJ connection diagram for your version of MJLJ hardware.
#Check the Molex connector itself, specifically that the pins in the connector are properly seated. If they are not pushed far enough into the plug, they can fail to make an internal connection at all, or intermittently.
#Perform the Hardware check in the Hardware Troubleshooting section.
#If you have access to an oscilloscope, you can verify the PIP signal on Pin 4 of the processor.
#You can also check the PIP signal using the AC setting of a multimeter. with the engine running you should see an AC reading that goes away when the engine is not running.
#Feel free to inquire on the [http://www.autosportlabs.org Forums]

==MJLJ Communicates with PC; Does not control advance==
If you can communicate with the MJLJ, but cannot get the MJLJ to control the EDIS module (i.e. you have connected a timing light and cannot observe the ignition advance changing), verify the following:

#Verify the MJLJ sees the PIP signal emitted from the EDIS module. The best way to verify this is to observe the realtime display, watching for RPM changes.
#If the configuration software shows an RPM reading, check the connections for the SAW signal, verifying that it is connected correctly. If you have an oscilloscope, watch for the SAW pulse coming from the MJLJ module; otherwise, watch for an AC signal using a volt meter.
#Check your wiring. Ensure you are connecting to the correct pins on the MJLJ molex connector and the EDIS module.
#Finally, inquire on the [http://www.autosportlabs.org Forums].

==Problems with USB-Serial Adapters==
===Communication stops when engine is running===
If the Configuration Software stops communicating with the MJLJ when the engine is started, try to physically distance the USB-Serial adpater from the MJLJ by inserting a serial extension cable. This may be especially bad for USB-Serial adapters that can plug straight into the MJLJ.

This problem typically manifests itself as the software reading rpm/advance/load data after the motor is started, then freezing in a matter of seconds.

The current theory is the unshielded electronics of the USB-Serial adapter is affected by electrical interference, presumably ignition noise. Some adapters are more sensitive than others; so far this has been reported on adapters based on the Prolific chipset.

Troubleshooting the MegaJolt Lite Jr.

2008-02-24T22:17:28Z

Alexander: /* MJLJ communicates with Configuration software; No RPM signal */

==Configuration software compatibility==

If you see an error message while attempting to communicate with the MJLJ, such as 'Could not open port' or 'Timeout reading runtime data' you can use a terminal program to directly test the MJLJ unit.

Here are the instructions for this testing procedure, using the common 'Hyperterminal' software.

===Troubleshooting with Hyperterminal===

Open up Hyperterminal. create a connection, and configure it to connect directly to the COM port you are using for the MJLJ.

When it asks for the communication settings, use the following:

Bits Per Second: 4800
Data Bits: 8
Parity: None
Stop Bits: 1
Flow Control: none

When you get to the main screen, send a capital 'C' to the controller. you won't see what you type echoed on the screen, but the controller should 'reply' with what looks like a sequence of random data. This simulates the Configuration software requesting the controller's current configuration

Pressing 'S' returns the current runtime status; You will see only a few characters displayed.

If the above does not work, or if Hyperterminal indicates a COM port or communications error:

#Use a different serial cable. The cable you're using might not be compatible serial cable, or may have a broken internal connection.
#Are you using the same serial port with other applications? Programs like synchronization software for hand-held devices like the Palm are known for keeping the serial port open, preventing other applications from accessing it.
#As a debugging step, try a different computer. This will at least let you know the MJLJ and software can communicate, and will help narrow down the source of the problem.
#If you're using a USB-serial adapter, make sure the latest drivers are installed, the driver shows no errors, and you know which COM port it was installed on. Often the USB-Serial adapter will install on a high COM port number, like COM6. You can verify this by accessing 'Device Manager' in Windows and viewing the properties of the USB-Serial adapter under 'Ports'.

If you can get the expected response from the MJLJ, then there is a configuration problem with the MJLJ software. Verify you have the correct COM port set under 'Options'. If the trouble persists, check for a newer version of the software, or inquire on the forums[http://www.autosportlabs.org] for additional help.

==Hardware Troubleshooting==
If you built the MJLJ from a kit and your controller does not communicate or otherwise doesn't seem to be 'alive', perform the following checks;

===Check Power===
*Verify you have an adequate power supply, correctly connected to the MJLJ unit. See the [[MJLJ_V3_vehicle_installation_guide|Vehicle installation guide]]
*With the unit powered up, check to make sure the correct voltage (+5v) is present at all of the power input pins of the integrated circuits and oscillator.

===Ensure sure the components are installed correctly===
*Diodes and capacitors installed with the correct polarity (capacitors marked with a '+' or '-' sign)
*Integrated circuits, oscillator and transistors with the correct polarity (orient the notch on the chip with the notch shown on the circuit board)
===Check for good solder joints===
*Carefully inspect the pins to make sure the solder connections are bright and flow completely around the pins and onto the pad.
*Ensure that you haven't accidentally lifted the pad away from the board and broken a solder trace.
*Check for solder 'bridges' where you might have solder across two pads, resulting in a short circuit.

==MJLJ communicates with Configuration software; No RPM signal==

If you can communicate with the MJLJ software but cannot get an RPM signal from the EDIS module-

#Check the connection between the EDIS module and the MJLJ. Ensure the PIP signal from the EDIS module is connected to the correct pin on the Molex connector. Review the MJLJ connection diagram for your version of MJLJ hardware.
#Check the Molex connector itself, specifically that the pins in the connector are properly seated. If they are not pushed far enough into the plug, they can fail to make an internal connection at all, or intermittently.
#Perform the Hardware check in the Hardware Troubleshooting section.
#If you have access to an oscilloscope, you can verify the PIP signal on Pin 4 of the processor.
#You can also check the PIP signal using the AC setting of a multimeter. with the engine running you should see an AC reading that goes away when the engine is not running.
#Feel free to inquire on the [http://www.autosportlabs.org Forums]

==MJLJ Communicates with PC; Does not control advance==
If you can communicate with the MJLJ, but cannot get the MJLJ to control the EDIS module (i.e. you have connected a timing light and cannot observe the ignition advance changing), verify the following:

#Verify the MJLJ sees the PIP signal emitted from the EDIS module. The best way to verify this is to observe the realtime display, watching for RPM changes.
#If the configuration software shows an RPM reading, check the connections for the SAW signal, verifying that it is connected correctly. If you have an oscilloscope, watch for the SAW pulse coming from the MJLJ module; otherwise, watch for an AC signal using a volt meter.
#Check your wiring. Ensure you are connecting to the correct pins on the MJLJ molex connector and the EDIS module.
#Finally, inquire on the [http://www.autosportlabs.org Forums].

==Problems with USB-Serial Adapters==
===Communication stops when engine is running===
If the Configuration Software stops communicating with the MJLJ when the engine is started, try to physically distance the USB-Serial adpater from the MJLJ by inserting a serial extension cable. This may be especially bad for USB-Serial adapters that can plug straight into the MJLJ.

The current theory is the unshielded electronics of the USB-Serial adapter is affected by electrical interference, presumably ignition noise. Some adapters are more sensitive than others; so far this has been reported on adapters based on the Prolific chipset.

MJLJ V3 vehicle installation guide

2008-02-24T21:55:59Z

Alexander: /* MAP Sensor operation */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====Using existing Vacuum Advance port====

Most vacuum advance takeoff ports are designed in such a way that vacuum is measured through a hole which is actually covered by the edge of the throttle plate, at idle. That is done to cut off all vacuum advance at idle, which in turn slows the engine and makes it easier to achieve stable idle with the tiny throttle plate opening used at idle. Vacuum measured on such a port, therefore, has no vacuum at idle, moves to maximum vacuum just off idle, and then decreasing vacuum as the throttle is opened further. The discontinuity just off idle makes such a port awkward to deal with on the load map.

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil to detect this pulse from. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternate approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.

MJLJ V3 vehicle installation guide

2008-02-24T21:40:12Z

Alexander: /* Using EDIS PIP signal */

==Parts you will need==

To complete your installation, you will need the following components. Most can be harvested from automotive salvage yards, acquired on ebay, or online vendors.

*EDIS module matching your engine type
**EDIS-8 for 8 cylinder
**EDIS-6 for 6 cylinder
**EDIS-4 for 4 cylinder
*Coil packs: Many use the matching Ford coil packs, but typically most coil packs that have closely matched primary and secondary coil DC resistance will work.
*VR Sensor: We suggest you use a Ford VR sensor- this guarantees best compatibility with the Ford EDIS module.
*Trigger wheel: Many adapt the trigger wheel removed from the crank pulley of a donor Ford engine- others machine the pattern into an existing wheel, or buy a pre-made wheel.

For those of you in the UK, a supplier of trigger wheels and EDIS parts can be found here: [http://www.trigger-wheels.com www.trigger-wheels.com]

''ToDo add table showing donor vehicles by EDIS module type''

==EDIS installation==

===Crank timing wheel and sensor installation===

The Ford EDIS ignition module is designed to work with a 36 tooth wheel, with 1 missing tooth to act as a synchronization reference for engine Top Dead Center.

When mounting the sensor wheel the EDIS module requires specific positioning of the sensor relative to the missing tooth, ''while the engine is at Top Dead Center''. The following table defines the sensor position relative to the missing tooth for 4,6 and 8 cylinder EDIS modules.

<center>
{| border = 1
|+ Sensor Position
|- bgcolor=grey
!Type!!Degrees BTDC
|-
|EDIS-4||90
|-
|EDIS-6||60
|-
|EDIS-8||50
|}
</center>

With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees after the missing tooth. Since the sensor wheel has a tooth (or the missing tooth) every 10 degrees, the sensor should be positioned N/10 teeth after the missing tooth (9 teeth after the missing tooth for 4 cylinder applications for example). Make sure you take into account the rotation of the engine: clockwise or counter-clockwise, when determining your sensor mounting.

The following graphic illustrates how the sensor position and missing tooth can vary relative to engine TDC- regardless of where the sensor is mounted, the missing tooth must be positioned accordingly.

<center>
[[Image:edis_wheel.gif]] 
'''''Shown: Relationship between engine Top Dead Center and sensor positioning. Wherever you place the sensor, the distance from the missing tooth must remain constant.'''''
</center>

The following photos illustrate an EDIS-4 installation on a Toyota 4AG engine. Notice the thickness of the sensor bracket designed to minimize harmonic vibrations which may affect the sensor signal. The crank pulley was machined down to accommodate the timing wheel from a 1997 Ford Escort, and then tack welded in place.
----
[[Image:edis_sensor_bracket.jpg|VR Sensor and bracket|320px]]
[[Image:timing_wheel_face.jpg|Machined crank pulley with timing adapted|320px]]
[[Image:timing_wheel_face_close2.jpg|Closeup view of adapted timing wheel|320px]]
[[Image:timing_wheel_end.jpg|Machined pulley with timing wheel adapted|320px]]
[[Image:timing_wheel_mounted.jpg|Modified crank pulley mounted with VR Sensor|320px]]
----

===EDIS and coil-pack installation===

Since the EDIS module can operate the engine by itself in a "limp-home" mode, with the advance fixed at 10 degrees BTDC, it's recommended you install the EDIS module and coil packs '''first''', and then verify your engine runs before wiring in the MJLJ.

Wire up the EDIS module and coil pack(s) using the following diagram, matching your engine type (EDIS 4 = 4 cylinder, EDIS 6 = 6 cylinder, EDIS 8 = 8 cylinder). Engines with 'even-fire' configurations are supported, which represents the vast majority of 4,6, and 8 cylinder engines in production.

<center>
[[Image:EDIS_Module_harness.png]] 
</center>

===EDIS Wiring notes and guidelines===

*Use shielded cable for the VR Sensor. Be sure to ground the shield as well. A 22-24 gauge, 2 conductor cable with a foil shield works well.
*Use 12-14 gauge wire for EDIS ground, power and coil pack connections.
*Note the VR sensor is polarized- you will not get spark from the EDIS module if it is wired backwards. If you don't see spark, try reversing the connection on the VR sensor.
*Minimize supply voltage variances and especially ground loop problems:
**It's strongly recommended you power the EDIS module and MJLJ from the same electrical circuit. Typically this will be +12V switched (Key to "on" position)
**'''Important! - Ground both the EDIS and MJLJ at the same point on the chassis.'''
* Capacitor attached to coil: The capacitor sometimes found attached to OEM coil packs can be safely omitted.

==Installing the MJLJ==
<center>
[[Image:MJLJ_V3_Wiring_Harness.png]]
</center>

===MJLJ wiring notes and guidelines===
*The MJLJ should be installed inside the passenger compartment. It's not designed to handle the temperature,vibration and moisture extremes of the engine bay.
*Use shielded cable for the PIP/SAW signal between the MJLJ and EDIS module. Be sure to ground the shield as well. A 2-conductor cable with a foil shield works well.
*Use 16 gauge wire for the MJLJ ground connection. 18-20 gauge wiring is fine for power and the other connections.
*For MAP based setups ignore the TPS connections.

===Load Sensing: Manifold Pressure Sensor (MAP) or Throttle Position Sensor (TPS)===

====MAP Sensor operation====
If your MJLJ is optioned with an onboard MAP sensor, find an appropriate spot on your manifold to reference a stable source of vacuum. Run a vacuum line from this location to the barbed connection on the MJLJ.

If you have multiple runners and throttle bodies / carburetors, you may need to buy/build a balance tube to average manifold pressure across all runners. Some opt to construct a miniature reservoir to smooth the pulses across all cylinders.

<center>
[[Image:adapting_map_sensor_for_multiple_runners.png]]
</center>

<center>
[[Image:adapting_map_sensor_for_multiple_runners_balanced_tubes.png]]
 
''Alternate technique which may offer a more balanced signal''
</center>

====TPS Sensor operation====
For a TPS setup, wire the TPS unit according to the diagram. Be sure to wire the sensor in such a way that the voltage going to the TPS input increases with throttle opening. If you are unsure, do not finalize the connection of these wires until you can verify operation using the PC software. For Firmware versions 3.1 and later, a calibration routine is available to correctly scale your throttle from 0 to 100%.

===Interfacing to Tachometers===

====Using the TACH OUT on the MJLJ====
Many tachometers can accept the signal emitted from the TACH OUT on the MJLJ module. This TACH OUT signal provides a 12V pulse for every ignition event. You may use this to provide the signal to compatible tachometers.

====Tachometers that require a high-voltage kickback pulse====

Some OEM-style tachometers detect the RPM signal by sensing the high voltage fly back pulse from the ignition coil. In distributor based setups, there is only one ignition coil to detect this pulse from. With a wasted spark system, this 'signal' is spread across multiple coils. As a result, you will need a way to combine these pulses across multiple coil packs to drive your tachometer.

The following circuit allows the fly back pulse to be detected across individual coil packs while still isolating the coils from each other.

<center>
[[Image:tach_circuit.jpg]] 
''OEM tachometer adapter circuit'' 
''If the above circuit does not work, try omitting the Zener diode.''
</center>

====Using EDIS PIP signal====

An alternate approach that appears to work with older 'Smiths' type tachometers is to share the PIP signal that is emitted from the EDIS module. The PIP output is a 12V square wave with a larger duty cycle than the TACH_OUT provided by the MJLJ. Simply wire the EDIS PIP output to both the MJLJ PIP input as well as the tachometer sense wire.

If this approach is used, you should check to make sure the MJLJ receives the PIP signal consistently, since the PIP line has extra current demand placed upon it. The current demands of the MJLJ PIP input is low, so it should work fine- and a few field reports have shown this. However, a quick check using the configuration software for consistent RPM readings would be prudent.

Note that there are two types of older Smiths tachometers: RVI - current sensing, and RVC - voltage sensing. These letters, and numbers indicating exactly which variant you have, are printed in small white lettering on the bottom of the face of the tachometer. RVI type tachometers work by routing the coil +ve supply wire through an inductive loop of wire inside the tachometer, and are not compatible with the MJLJ. If you have an RVI type tachomoter, you can replace it, have an add-on circuit board added inside, or replace all the inside working parts with those from a newer tachometer ie retain the original face, but change everything else. For that approach you need a donor which has the same angular swing per 1000rpm, as the Smiths gauge.

===User defined outputs and Shift Light===

The four user-defined outputs provided by the MJLJ can be set to trigger on either RPM or Load thresholds. The separate 'shift light' output triggers only on RPM, but otherwise behaves identically to the user outputs.

Starting with V3.1 firmware the user outputs have hysteresis control. For RPM, the hysteresis threshold is 100 RPM; for Load, the threshold is 1 KPa or 1% TPS.

The configuration of these outputs is provided by the PC configuration software, covered in a later section.

Each output can supply up to 500mA, which is enough to drive LEDs, small incandescent lamps, relays, and small solenoid valves. If you are unsure on the amount of current drawn by the accessory, you can power it manually and measure it's current using a Volt-Ohm-Amp meter.

Accessories that have a higher current demand can be controlled by relays, with the MJLJ output driving the relay.

Should you exceed the current capacity of one or more of the user defined outputs and damage the IC that drives the user outputs (ULN2003 darlington array), replace the chip with a new unit- it is socketed for this specific reason.

<center>
[[Image:MJLJ_User_output_examples.png]]
</center>

===Enabling Option Switch (For MJLJ firmware > 3.1.0)===

For MJLJ firmware versions 3.1.0 and later, the Option input is used to enable on-the-fly switching between Ignition Configurations, controllable via a dash mounted switch.

To enable this feature you must have controller firmware V3.1.0 or later installed, and the feature must be enabled in the controller (covered later). Wire the switch based on how your MJLJ is optioned; use the following diagram as a guide:

<center>
[[Image:MJLJ_V3_wiring_option_switch.png]]
</center>

===Rev Limit control===

The ford EDIS system offers no direct ability to disable the ignition coils in an over-rev condition. The indirect way to enable this is through an external circuit that disables power to the ignition coil(s).

The MJLJ offers an output that triggers on the configured rev-limit. An additional feature of the Rev Limit functionality is tha the ignition advance automatically goes to zero 100 RPMs before the configured limit, offering a softer approach to the hard limit.

We are currently developing an external board that accepts this rev limit output and disables the ignition coil(s) when activated.

Current experimental techniques involve either using a mechanical relay to cut power to the coils, or tie the coil (-) to +12V through a current limiting resistor, suppressing spark by preventing the sudden collapse of the coil's magnetic field.

==MJLJ Operation==

===Verifying MJLJ operation===

After you've double-checked the wiring of the MJLJ, connect a timing light and start the engine. You should observe the ignition advance changing in precise steps in response to throttle changes. If this is what you observe, congratulations!! This may be your first time observing the benefits of precision crank-fired ignition!

If the advance does not change, or appears jittery or unstable, verify your MJLJ installation, especially the PIP / SAW connection, proper grounding and cable shielding.