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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Ignition Control Module: Description and Operation

The Electronic Ignition Control Module (ICM) monitors the CKP sensor signals and based on these signals, sends a 7X reference signal to the PCM so that correct spark timing and fuel injector control can be maintained during all crank and run conditions. Since the PCM controls spark timing and ignition control during crank and run, there is no bypass mode.

The ICM is not repairable. When a module is diagnosed to be faulty, it is replaced as a separate component.