Question about 1999 Cadillac DeVille

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Theft mode light

Last solution to fix problem theft lite comes on and car shuts down.been towed to cadillac dealer 4x's now.i brought your solution to him.get locksmith with v.a.t.s. to check key to wires on the bottom. he didn't get locksmith,but changed harness,couplings,ignition started drove it home, theft mode light came back on and car is sitting here for 3 days. won't start.he says he keeps replacing parts and can't figure out what is wrong with it.but says we should trade it in and get another car. what good will that do the next person that buys it?we are retired and our car is paid for. god only knows what his bill is going to be for a car we can't start.thank you for any help you can give us.

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Has anyone changed the part of the ignition switch that reads the key value and sends it to the anti-theft module, it this part malfunctions it will lock you out, and you will be unable to start the car, they are a known fault for all GM lines with factory anti-theft systems, it is part of the ignition switch, but I believe that it alone can be replaced, call your local dealer and ask about the sensor for the VATS key in the ignition, they should know what the part is formally called.

Posted on Sep 29, 2008


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