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Ignition Control Module: Description and Operation

Ignition Coil Assembly And CKP Sensor:




Sensor To Crankshaft Reluctor Relationship:




Firing Order:






The Ignition Control Module (ICM) monitors the Crankshaft Position (CKP) sensor signals and based on these signals sends a reference signal to the Powertrain Control Module (PCM) so that correct spark and fuel injector control can be maintained during all driving conditions. During cranking, the 1CM monitors the "sync-pulse" to begin the ignition firing sequence and below 4O0 RPM the module controls spark advance by triggering each of the two ignition coils at a pre-determined interval based on engine speed only. Above 400 RPM the PCM controls the Ignition Control (IC) circuit and compensates for all driving conditions. The ICM must receive a "sync-pulse" and then a crank signal in that order to enable the engine to start.

NOTE: The ICM is not repairable. when an ICM is replaced, the remaining components must be transferred to the new module.