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Q: Car won't turn on

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My car won't turn on. Someone tried to steal it when I was in a store, and when we came back, the lights were on, and the doors were unlocked. We thought the battery was dead, but the radio turns on fine. When we try to start it, it goes into theft deterrent mode with the locked car symbol, which won't turn off no matter what we do. We've tried leaving the key in the door, leaving the key in the ignition in accessory mode, and even tried to dearm it via radio. Any advice?
My car has an automatic transmission.

Hello, thank you for writing in. I am sorry to hear about your situation! The very first thing to do is check the owner’s manual for any information about the anti-theft system (if you have not already done so). If you have a spare key, you will want to try starting it with that one instead. The anti-theft module, or the procedures you have attempted, may have messed with the programming for your main key. Make sure the battery is fully charged and allowing the computer to use the amount of power that it needs to perform these functions. If you have any aftermarket parts on the vehicle, make sure they are disconnected if possible. For more help starting the vehicle, contact our service department to schedule an appointment to meet you at the vehicle.

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