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System Description

The vehicle is equipped with an immobilizer system (type ill) that will disable the vehicle unless a programmed ignition key is used.

This system consists of a transponder located in the ignition key, an immobilizer control unit-receiver, an indicator light, and the PCM.

When a programmed key is inserted in 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 through the immobilizer control unit-receiver to the PCM, and the PCM enables the fuel and ignition systems. The transponder codes are embedded in the immobilizer control unit-receiver (fixed code). A handshake between the PCM and the immobilizer control unit-receiver is required at the PCM repair and replacement, and all keys are required at the immobilizer control unit-receiver repair and replacement.

Fig 1: Immobilizer Control Unit-Receiver System Description
G03642266Courtesy of AMERICAN HONDA MOTOR CO., INC.