Ford EDIS technical information

Revision as of 19:33, 10 June 2007 by DraZ2y (talk | contribs)

cheap diazepam cheap xenical nokia ringtones qwest ringtones zanaflex online diazepam online verizon ringtones free motorola ringtones order lortab prozac online ericsson ringtones but ortho cheap cyclobenzaprine cheap celexa free ringtones phentermine free cool ringtones cheap prozac free qwest ringtones cialis online sprint ringtones nexium online real ringtones sagem ringtones tracfone ringtones free nokia ringtones free punk ringtones mp3 ringtones sony ringtones ativan online but hgh free midi ringtones alltel ringtones cheap flexeril sony ericsson ringtones motorola ringtones vicodin online free tracfone ringtones buy soma levitra online free motorola ringtones cheap didrex cheap sildenafil pharmacy online online zoloft online hydrocodone online free sony ringtones cingular ringtones viagra buy paxil ambien online buy lortab order hydrocodone vigrx online cheap ativan hgh online sildenafil online buy viagra ortho online nextel ringtones lisinopril free funny ringtones free sony ericsson ringtones buy vicodin hydrocodone order ativan mono ringtones clonazepam levitra free sprint ringtones cialis online sony ringtones cheap levitra zanaflex online phentermine celexa online ultracet online wwe ringtones free sharp ringtones buy norco soma online cheap ultracet free cingular ringtones cheap adipex cheap xenical cheap albuterol cheap tenuate cheap ortho free music ringtones sagem ringtones cheap lisinopril meridia online cheap propecia cheap vigrx cheap diethylpropion cheap albuterol mp3 ringtones meridia online free ringtones cheap ultram soma online cheap lortab cheap sildenafil free nextel ringtones cheap lorazepam free funny ringtones diethylpropion online free ringtones funny ringtones cingular ringtones cheap soma nokia ringtones clonazepam online zyban online clomid online buy prozac online valium order lisinopril meridia online buy tramadol sharp ringtones free midi ringtones flexeril online real ringtones celexa online zoloft online free nextel ringtones ericsson ringtones free music ringtones mtv ringtones order ultram buy valium viagra online lorazepam online cheap cialis cheap phentermine buy nexium samsung ringtones cheap norco meridia online sprint ringtones buy rivotril order carisoprodol carisoprodol online cyclobenzaprine online free qwest ringtones free qwest ringtones cheap fioricet verizon ringtones punk ringtones cheap hoodia pharmacy online online tracfone ringtones tramadol cheap rivotril tramadol online didrex online cheap fioricet music ringtones cheap albuterol free nokia ringtones buy viagra buy alprazolam buy xenical pharmacy online online free funny ringtones order zanaflex free ericsson ringtones cyclobenzaprine online adipex online cheap xanax free alltel ringtones free qwest ringtones ultram online sonyericsson ringtones free samsung ringtones cheap lortab free mono ringtones free samsung ringtones zyban online cheap celexa free funny ringtones wwe ringtones cheap rivotril but clomid buy fioricet buy hgh cheap lipitor cheap hoodia clonazepam online cool ringtones tenuate online cheap vicodin real ringtones free sonyericsson ringtones buy hoodia buy tramadol nextel ringtones cheap alprazolam ambien online ==Ford EDIS general information== The Ford EDIS system consists of a controller module, coil packs, a crank trigger wheel and matching variable reluctance sensor. Running alone, the EDIS module will fire the spark plugs at 10 degrees BTDC, operating in it's "limp home mode".

EDIS system diagram.png

Normal operation involves interaction between the engine management system and the EDIS module, using the PIP and SAW as communication lines. After each ignition event, the EDIS module requests the current ignition advance value from the engine management unit using the PIP line. The engine management system calculates the current ignition advance and signals it back on the SAW input of the EDIS module. To communicate the advance value, the SAW reply signal is a pulse with a duration that corresponds to the amount of degrees advance.

The formula for calulating the SAW pulsewidth is as follows:

SAW Pulse width (uSec) = 1536 - (25.6 x (desired spark advance in degrees)) 
Range: 64 - 1792us (57.5° BTDC to 10° ATDC)
Resolution: 4us (5/32nd of a degree)

The MegaJolt Lite Jr emulates the Ford engine management system, communicating the desired ignition advance value to the EDIS module calculated from it's internal configuration.

Trigger wheel and sensor mounting

Each EDIS application requires a different sensor mounting configuration. Use the following table to determine the correct sensor position in relation to the missing tooth and the engine's TDC.

Sensor Position
Type Degrees BTDC
EDIS-4 90
EDIS-6 60
EDIS-8 50


With the Engine at TDC for cylinder #1, the sensor should be positioned 'N' degrees before the missing tooth. Make sure you take into account the rotation of the engine: clockwise or counter-clockwise when determining your sensor mounting.

For example: On an EDIS-4 application with the engine at Top Dead Center (TDC) - if the missing tooth is aligned with TDC (pointing up, or aligned with the crank pulley key), the sensor should be aligned with the center of the tooth 90 degrees BTDC. If this was a typical clockwise rotating engine, the sensor would be positioned 90 degrees to the left side of the crank sensor (9 o'clock position), when viewed facing the crank.

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.


As long as the relation between the missing tooth and sensor remains constant, you can position the sensor at your convenience. In my case with a toyota 4AG motor, it was easier to mount the sensor on the exhaust side of the block, so I oriented the missing tooth so it pointed down, or opposite, of TDC. The sensor was still mounted 90 degrees BTDC, at the 3 o'clock position when facing the crank.

Interfacing with OEM Tach

Many OEM tachometers operate by sensing a high voltage kickback pulse from the coil. You can find out if you have one of these tachometers by connecting your auto's tach input to the MJLJ tach output. If you don't see activity on on the gauge then it is likely that your unit requires this HV kickback pulse.

If you are converting from single-coil distributor setup, your OEM tach will need to see the HV kickback pulse from both EDIS coil packs. Here's a simple circuit on how to extract both coil pack's HV pulse while maintaining electrical isolation.

Tach circuit