I have a Passat GT VR6 (1991/92 model so early VR6), I can scan the car while only the ignition is on.
When I try to scan it while it's running I get an error message. It tels me (among other things) to check connection, maybe not connected to right COM port etc........but all connections are correct and working.....
Any ideas?, or can't the early VR6's be scanned while running?
EDIT: Also shouldn't it be able to do any communication with the ABS ECM? or is this only for later models?