diagnostic tips for vats (pass keyII)

[steven david]

start and stall condition showed a pass key error code on my 94 buick. lock cylinder and key ohmed out the same as new from dealership, leaving me to believe it was the anti-theft module.rather than buy one for $340, i purchased a by-pass module on line for $30.it was only for the fuel enable part of the anti-theft module. it was not the problem, but it did force me to trace the blue (normally) wire from module to pcm. a 2.89 volt reading at the pcm seems to indicate an operable anti-theft module. (again, the fuel enable meaning injector pulse).the problem turned out to be the pcm .

[Ratt643]

Where did you purchase the by-pass module for the PASS-II on your Buick?
Mine is cuttting off the injectors after it starts and I don't know that I can get a used anti theft module with a key. Thanks

[steven david]

got it off the webb. try GM vats bypass,it came in the mail in three days. again, it turned out that it was the ECM in my case. after installing the by-pass and still stalled , is when I checked the voltage from the by-pass and compared it to the voltage from the anti- theft device(vats) they were the same, which eleminated the whole vats system from key to ECM