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 igniter has the section to judge the severity of detonation and a section to control the ignition timing. Based on the signal from the detonation sensor, the igniter judges detonation and controls ignition timing. The igniter incorporates a fail-safe feature which retards the ignition timing by a fixed angle, except at idle, to protect the engine in the event of detonation sensor failure.