System Description

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

This system consists of a transponder, an immobilizer control unit-receiver, immobilizer indicator, imoes unit, and the PCM.

When the immobilizer key 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 PCM to supply power to the fuel pump circuit. A handshake with the HDS is required at PCM or imoes unit repair or replacement, and all keys are required at immobilizer control unit-receiver repair or replacement.

Fig 1: Immobilizer System Communication Diagram

Courtesy of AMERICAN HONDA MOTOR CO., INC.

• If a programmed 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 to LOCK (0).
• When the ignition switch is turned to LOCK (0), the indicator will blink for 5 seconds to signal that the unit has reset correctly, then the indicator will go off.

IMMOBILIZER INDICATOR BLINKING PATTERN: 

IGNITION SWITCH		Courtesy of AMERICAN HONDA MOTOR CO., INC.
PROGRAMMED KEY INSERTED	INDICATOR	Courtesy of AMERICAN HONDA MOTOR CO., INC.
WRONG KEY INSERTED	INDICATOR	Courtesy of AMERICAN HONDA MOTOR CO., INC.