Q: Lost key won't start

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I lost my key so I bought a new key cylinder and it won't start and on the dash it says theft and that's the alarm how do i start it

My car has 176000 miles.
My car has an automatic transmission.

Hi there, thanks for writing in. The key is programmed to disable the theft system and if you replace the ignition lock and key it will not disable the system unless you have the system reprogrammed to work with the new key. You will need to have a dealer program the keys to work in your vehicle.

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