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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System Description

IMMOBILIZER CONTROL SYSTEM

DESCRIPTION




The immobilizer system is an anti-theft device which enables starting to be possible only when the mechanical and wireless secret codes are aligned simultaneously.

The transponder built in the ignition key signals its unique frequency code and at this time the ICM compares it with the memorized code.

When the codes are aligned, the ICM sends signals to the ECM so that starting is possible.

ICM: Immobilizer Control Module
ECM: Engine Control Module

System Block Diagram:





Components:




Components: