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Circuit Description

Immobilizer System

System Description


The vehicle is equipped with an immobilizer system that will disable the vehicle unless the proper ignition key is used. This system consists of a transponder located in the ignition key, an immobilizer control unit-receiver, an indicator, the imoes unit and the ECM/PCM.

'04-06 models

when the immobilizer key (programmed by the HDS) is inserted in the ignition switch turned to the ON (II) position, the immobilizer control unit-receiver sends power to the transponder in the ignition key. The transponder then sends a coded signal back to the immobilizer control unit-receiver which then sends a coded signal to the ECM/PCM to supply power to the fuel pump circuit.






'07-08 models

When the immobilizer key (programmed by the HDS) is inserted into the ignition switch and turned to the ON (II) position, the immobilizer control unit-receiver sends power to the transponder in the ignition key. The transponder then sends a coded signal back to the immobilizer control unit-receiver which sends a coded signal to the imoes unit, which confirms the code and signals the ECM/PCM to supply power to the fuel pump circuit. A communication agreement with the HDS is required at the ECM/PCM or the imoes unit after repair or replacement. When replacing the immobilizer control unit-receiver, all keys are required to be registered into the new control unit-receiver. Any keys that were not registered in the control unit-receiver will not start the vehicle.






- If the proper key has been used, the immobilizer indicator will come on for about 2 seconds, then go off.
- If the wrong key has been used or the code was not received or recognized by the unit, the indicator will come on for about 2 seconds, then it will blink until the ignition switch is turned OFF.
- If the ignition switch is turned OFF, the indicator will blink for about 5 seconds to signal that the unit has reset correctly, then the indicator will go off.