98 Cavalier Theft System On

We have a 98 Cavalier and we were doing some work to it. We replaced some leaking gas lines and replaced some dash pieces. We had to unhook the dash cluster to do so and now when we start the car the theft system comes on and shuts the car off. The car is still starting but once the theft system kicks in it stalls out. Does anyone know how to fix this issue WITHOUT taking it to a dealer? My friend had to take his in before and they charged over $300 to fix it and its an old car with high miles and I dont have that kind of money to spend on it. Any help would be GREATLY appreciated.

I would suggest starting with your owner’s manual. Not all cars are the same, but at least some will have a note in there about the code needed to reset things.

Good Luck.

call the dealer and ask for the re-set code and proceedure. If they wont tell you, call around and see if you can find a decent shop that will.

You need to do the key re-learn process. With the doors closed leave the ignition on for 10 min. the theft light should go out. Better if you google Passlock key relearn as I can’t find my exact instructions. Don’t go to Dealer, this can be dealt with, I am looking for my instructions.

Unplug the battery then the ECU…let it sit for 10-15 minutes then plug the cluster, battery and computer back in and you should be set.