Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Immobilizer Control System

IMMOBILIZER CONTROL SYSTEM
The purpose of the immobilizer system is to provide an additional anti-theft to the vehicle which is installed in, preventing it from an unauthorized use. Checking of user authorization is done by use of an ignition key which head integrates a crypto-transponder.

In case of a blocked Immobilizer system (unauthorized key), the ECM control unit locks the engine control by cutting off the ignition circuit and the injector circuit. To secure the system, the information exchanged between BCM and ECM through the K-line is coded. The key teaching and the diagnostic of both control units (BCM & ECM) are realized by diagnostic services with the diagnosis tool.

Block Diagram - Immobilizer Control System:




BLOCK DIAGRAM