Engine Immobilizer Systems: Description
WARNING:
Deactivate air bag system before performing any service operation. See AIR BAG RESTRAINT SYSTEMS article. DO NOT apply electrical power to any component on steering column without first deactivating air bag system. Air bag may deploy.
NOTE:
If a problem exists in the engine immobilizer system, a Diagnostic Trouble Code (DTC) may be stored in the Engine Control Module (ECM), but the Malfunction Indicator Light (MIL) on the instrument panel will not come on. MIL may also be referred to as the CHECK ENGINE light.
Engine immobilizer system is a theft deterrent system that disables engine from starting by not allowing fuel injector operation and ignition system operation unless ignition key identification code matches identification code stored in the Engine Control Module (ECM). Engine immobilizer system consists of ignition key with built-in transponder chip, transponder key coil located on ignition lock cylinder, transponder key amplifier located near upper steering column bracket, key unlock warning switch on ignition lock cylinder and ECM. See Fig 1.