how DO you unlock the theft system
Call a locksmith
You'll need to have it towed to the Chevy dealer. Sounds like the anti-theft module is no longer recognising the transponder key. Inquire about the GM ignition switch recalls. See if your Cavalier is involved. If so you can probably get it fixed for free. HTH. -Jim
My Cavalier is a 1998. This car has a "pass lock" theft system which was tripped and it would start but then die after a few seconds. I found out the way to re-set it is to crank the motor, let it start and stall, but leave the ignition engaged. The theft light then blinks for 10 minutes, then stays on solid. At that point, turn the ignition off, wait 5 seconds, then turn on the ignition again and the car starts up. Worked for me. Good luck!
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