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System Description

The vehicle is equipped with type IV immobilizer system that will disable the vehicle unless the programmed ignition key is used.

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

When the 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 to the immobilizer control unit-receiver which then sends a coded signal to the ECM/PCM. The code is a rolling type embedded in the receiver instead of the ECM/PCM.

Fig 1: Identifying Immobilizer System Description
G03662296Courtesy of AMERICAN HONDA MOTOR CO., INC.