Engine Immobilizer Systems: Operation

Transponder chip is incorporated into the grip area on the ignition key. When ignition key is inserted into the ignition lock cylinder, the Engine Control Module (ECM) instructs transponder key coil on ignition lock cylinder to supply an electromagnetic energy that enables transponder chip to transmit an ignition key identification code signal.

Transponder key amplifier then amplifies the ignition key identification code signal and delivers ignition key identification code signal to the ECM. The ECM compares received ignition key identification code signal to identification code stored in the ECM. If ignition key identification code and identification code in the ECM match, ECM will allow fuel injector operation and ignition system operation. If ignition key identification code and identification code in the ECM do not match, ECM will not allow fuel injector operation and ignition system operation.

Engine immobilizer system is set each time ignition key is removed from ignition lock cylinder. When engine immobilizer system is set, the SECURITY indicator light will flash once every second to indicate the system is set. SECURITY indicator light is located near the clock at the center of instrument panel, just below the stereo. For information on programming of ECM and ignition key identification key codes, see IGNITION KEY REGISTRATION  under PROGRAMMING. If a problem exists in the engine immobilizer system, a Diagnostic Trouble Code (DTC) may be stored in the ECM, but the Malfunction Indicator Light (MIL) on the instrument panel will not come on.