hi, ive done vr6 engine swap in my mk2 but i can't get OBD port to work and its not communicating, does anyone know what problem it could be i just don't know where else to look ? thanks
first off does it have the immobiliser box or not, and what kit are you using to scan the ecu? some aftermarket scan tools arent compatible with VW ecu. the port needs permanent live to pin 16, earth to pin 4 and diagnostics to pin 7. on non-immo ecu this goes straight to ecu pin 43, with immo it is connected to the immo box then the box is connected to ecu pin 43. really early vr6 have a 2nd yellow wire from ecu pin 21 to port pin 15
VCDS or even VCDS lite will work. Get a cheap KKL cable from ebay and download lite from ross-tech. https://www.ross-tech.com/vcds-lite/download/index.php It was only the true USA ECUs that are OBD2 compliant even though a lot of people call the later 95 ECUs 'OBD2' See https://www.gendan.co.uk/article_1.html
