The immobilizer system protects your vehicle from theft. If an improperly coded key (or other device) is used, the engine’s fuel system is disabled.
Mechanical key If you lock the driver’s door with a mechanical key, all vehicle doors will lock. If you unlock the driver’s door with a mechanical key, you can open and close the driver’s door only.
Replacement 1. If the compressor is marginally operable, run the engine at idle speed, and let the air conditioning work for a few minutes, then shut the engine off. 2. Disconnect the negative (-) battery terminal.