System Description

The immobilizer system prevents the engine from starting unless the proper keyless remote or built-in key is used. The immobilizer system consists of the immobilizer control unit-receiver, the keyless remote, the keyless access control unit, the transponder in the built-in key, the imoes unit, and the PCM.

When the built-in 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 built-in key. The transponder then sends a coded signal back to the immobilizer control unit-receiver which then sends a coded signal to the PCM and the imoes unit. The PCM and the imoes unit identify this coded signal, then the fuel supply system is enabled.

When using the keyless remote, the remote sends a signal to the keyless access control unit. The keyless sends a coded signal to the imoes unit. The imoes unit determines if the correct code is used, and if so, the fuel supply system is enabled.

Fig 1: Immobilizer System Communication Diagram

Courtesy of AMERICAN HONDA MOTOR CO., INC.

• If the proper key or remote is used, the immobilizer indicator comes on for about 2 seconds, then goes off. When the ignition switch is turned to LOCK (0), the indicator blinks for about 5 seconds to signal that the unit has reset correctly, then the indicator will go off.
• If the wrong key is used or the code was not received or recognized by the unit, the indicator comes on for about 2 seconds, then it blinks until the ignition switch is turned to LOCK (0).
• If the client has lost their keys and remotes, and cannot start the engine, contact Acura Client Services.

IMMOBILIZER INDICATOR LIGHTING PATTERN: 

Fig 2: Immobilizer Indicator Lighting Pattern

Courtesy of AMERICAN HONDA MOTOR CO., INC.