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

Igniter Unit:






The igniter unit, mounted on the right strut tower, controls ignition timing and is itself controlled by the ECU. The ECU contains memories for basic ignition timing at various engine speeds, manifold pressures and coolant temperatures. The ECU retards or advances the timing to match these memories through the igniter unit.