Q: My car will not start and the message says "theft". 2004 Pontiac Grand Prix

asked by on December 10, 2016

car always ran fine but now, my car wont let me start it up it keeps saying "will not start due to theft system" do you have any idea what to do? the car is an 04 Pontiac grand prix Gt

My car has 258000 miles.
My car has an automatic transmission.

Hello. It sounds like you have an issue with the anti theft system malfunctioning. This commonly occurs on this vehicle. Most of the time this is caused by a failure in the key sensor in the ignition key cylinder. It can also be an issue with the theft module itself. I usually start by resetting the system to see if it starts. If the problem persists then I test the key sensor and replace it if it is bad. If that is also fine then the issue is usually in the module which would need to be replaced and programmed. Anti theft issues are best repaired by the dealer.

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