That sounds like a typical passlock problem. Passlock is your theft deterrent device.
When your car doesn't start, does " œsecurity' flash on the dash? If so that would confirm a passlock problem.
There're a few things you can do:
* Go to a dealer and get charged a ridiculous amount of money for a diagnosis and a fix that may or may not work.
* Try the GM reset procedure for passlock:
"Â Turn ON the ignition, with the engine OFF.
"Â Attempt to start the engine, then release the key to ON; the vehicle will not start.
"Â Observe the security telltale; after approximately 10 minutes the telltale will turn OFF.
"Â Turn OFF the ignition, and wait 5 seconds.
"Â Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes; the vehicle is now ready to relearn the Passlock Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.
Important: The vehicle learns the Passlock Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
* Bypass it (check online for infos)
Friday, March 12th, 2021 AT 9:19 AM
(Merged)