OBD CAN install

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Ignitron ECU suppords OBD-II communication (ISO 15765-4 CAN 11bit / 500kbaud) to ensure connection to aftermarket race dashes and displays which read vital information about the vehicle (f.eg actual RPM, vehicle speed, coolant temperature, intake air temperature, manifold pressure, ...) via OBD. Either you use a wired connection or an ELM327 based bluetooth interface with a tablet or phone application.


OBD female connector (connector side).
A standard female OBD connector will be needed, with at least four wires connected to the appropriate pins;

• 4 - Ground
• 6 - CAN hi
• 14 - CAN lo
• 16 - +12V (constant)

CAN hi can be found on pin 60 of the ECU, CAN lo can be found on pin 58 of the ECU. These two wires needed to be twisted (not connected) together and routed that way from the ECU to the OBD connector, this way the signals will be more immune to electromagnetic interference!

After installing the OBD connector, the OBD communication has to be enabled in the ECU as it is disabled by default!

If Ignitron ECU has been installed in a VW/AUDI/SEAT/SKODA 1.8 20VT car which already has an OBD connector, the powertrain CAN network still have to be wired in manually, as they did not install it in the factory! The OEM engine management of these cars does not communicate via CAN with the diagnostic equipment, but on the slower and obsolete K-line instead (which is not supported by Ignitron ECU)!

Inside the car, the wires of the powertrain CAN network can be found at the dials/instruments for example (they go into the green connector), but they may also show up elsewhere; they go out to the ABS/ESP controller, too. You can connect to the CAN bus at any point! The powertrain CAN wires can be easily identified; orange/black (CAN hi) and orange/brown (CAN lo) are twisted together! On cars with non CAN bus compatible instruments (pre 2001 cars with narrowband O2 sensor) it is more practical to search for the powertrain CAN at the ABS controller, perhaps at the Haldex loom, in worst case at the engine control unit (pin 60: CAN hi, pin 58: CAN lo).

Harness of the green connector for the instruments, sliced, after soldering.

The two extra CAN wires installed into the OEM OBD connector.

Pins 6 and 14 are missing in the factory OBD connector, therefore you will need to buy them (or the whole female connector itself) first from a scrapyard or a webshop selling automotive electronic connectors before attempting to fit the two new wires.