OBD2CAN RJ45: Difference between revisions

Revision as of 16:49, 8 November 2019

Introduction

The OBD2CAN OBDII Legacy Adapter translates your car's legacy OBDII interface into a CAN OBDII interface, transparently - effectively modernizing your car's OBDII interface.

This means systems expecting a modern CAN OBDII interface can work with any OBDII enabled vehicle (1996 - present).

Supported systems

RaceCapture/Track
RaceCapture/Pro (MK3, MK2)
RaceCapture/Apex
Any device that can only communicate with CAN OBDII ECUs, including some AIM systems, and others.

Optimized to get the best performance out of your ECU

The OBDII Legacy adapter automatically tunes itself to get the best performance, pulling data as fast as your ECU will allow. Note, the performance will vary based on the ECU and OBDII protocol supported.

Supported OBDII protocols

J1850 PWM
J1850 VPW
ISO 9141-2
ISO 14230-4
CAN (pass-through)

If your car is 1996-2007, it uses one of the protocols supported by the OBDII legacy adapter.

Note: when connected to a CAN OBDII vehicle, the CAN signals are passed through, and the OBDII legacy adapter is effectively bypassed.

What channels will I get?

Since the OBDII legacy adapter translates any PID query it receives, you'll get whatever SAE standard channels that your car's ECU supports - channels such as RPM, Throttle Position, Engine Temperature, Manifold Pressure, Fuel Level and possibly more, depending on what your makes available. You can find out all of the channels available on your vehicle by using a cheap OBDII Bluetooth adapter and the free Torque app and go into Adapter Status and scroll down to Available sensors.

Setting up with RaceCapture

Plug the included cable into the OBDII Legacy Adapter.
Plug the other end of the cable into your RaceCapture system.
- Note: If you are using RaceCapture/Apex, you will need to create a custom cable for CAN high and CAN Low - see the pinout diagram.

Important note for RaceCapture/Pro MK2: The +12v connection on the RJ45 is connected internally to the +12v on the terminal block on RaceCapture/Pro MK2. It's recommended you only power via one source - RJ45 or terminal block. If you have both connected at the same time, you may cause back-feeding of power through RaceCapture/Pro, which may cause damage to the unit. Notes:

You can disable the 12v power wire on the RJ45 connection to the OBDII legacy adapter by cutting the appropriate wire in the RJ45 cable. See the color codes for a guide on which wire to cut.
RaceCapture/Pro MK3 has internal protection diodes which avoids this issue.

Plug the OBDII Legacy Adapter into your car's OBDII port.
Connect the RaceCapture app to your RaceCapture unit and read the current configuration.
Navigate to Setup
On the CAN Bus page Turn on CAN in RaceCapture setup and choose 500KBPS for CAN 1

If you have more than one CAN device or want to move this from CAN1 to CAN2, see the page on Splitters and Crossover Cables.

On the OBDII page: Turn on OBDII, and add some initial channels using the (+) button.
- RPM, EngineTemp and TPS are recommended starting channels.

Write the configuration back to your RaceCapture system.
Start your engine and navigate to the Raw Channels page of the Dashboard view.
Watch for your data to appear!

Other devices

Since the OBDII Legacy adapter translates standard CAN OBDII queries, it can work with upstream devices that only work with CAN OBDII protocols, such as certain AIM systems.

To connect the upstream system, connect the CAN High, CAN Low and ground connections from the OBDII Legacy adapter to the data system you are working with.

Custom Cable

You can build a custom cable for power and CAN bus using a standard CAT-5 ethernet cable with an RJ45 connector. Wire up using the following color codes:

Note: These color codes assume EIA-T568B RJ45 cable (check printing on the cable to confirm)

Power, ground and CAN bus connections
Connection	(RJ45 cable)
+12v	Brown
Ground	Orange/White
CAN 1 High	Orange
CAN 1 Low	Green/White

Specifications

Mechanical

Cable Length: 6 ft (1.8 M)
Compact module plugs into your OBDII port
RJ45 connection to RaceCapture/Pro or RaceCapture/Track; custom wiring to RaceCapture/Apex.

Pinout

Supported Protocols

J1850 PWM
J1850 VPW
ISO 9141-2
ISO 14230-4
ISO 15765-4 CAN (pass-through)

Power

Power consumption: 100mA
Pass-through power provided to downstream systems: 1A Max supply.

@@ Line 55: / Line 55: @@
 * On the CAN Bus page '''Turn on''' CAN in RaceCapture setup and choose '''500KBPS''' for CAN 1
 [[Image:obd2can_CAN_setup.png|640px]]
+If you have more than one CAN device or want to move this from CAN1 to CAN2, see the page on [[Multiple_CAN_Systems#RJ45_Splitter|Splitters and Crossover Cables]].
 * On the OBDII page: '''Turn on''' OBDII, and add some initial channels using the '''(+)''' button.
 ** RPM, EngineTemp and TPS are recommended starting channels.