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Q: What is the immobilizer system?

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What is the immobilizer system?

A: The immobilizer system is an antitheft devi...

The immobilizer system is an antitheft device. It’s designed to prevent any key but one programmed for your car to start the ignition. If a key that isn’t programmed correctly (or that has lost its programming because of a dead battery) is inserted into the ignition, the fuel pump will be disabled and the car won’t start.

If your key is working, the green immobilizer light on your dash should light up briefly when you crank the engine and then turn off. However, if the light flashes and the engine won’t crank, it means the immobilizer system doesn’t recognize the key.

Remove the key from the ignition and try it again, but the key may need to be reprogrammed.

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