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Ignition Control Module: Description and Operation

IGNITION COILS AND IGNITION CONTROL (IC) MODULE

Ignition Coils And Ignition Control Module (ICM):




Three dual tower ignition coils are mounted to the IC module, and are serviced individually. The IC module performs the following functions:
^ Receives and processes the signals from the 7x CKP sensor
^ Determines the correct coil triggering sequence, this coil sequencing occurs at start-up, and is remembered by the IC module. After the engine is running, the module will continue to trigger the coils in the correct sequence.
^ Determines the correct direction of the crankshaft rotation, and cuts spark and fuel delivery to prevent backfiring if this condition occurs
^ Produces and sends low resolution engine speed signals to the PCM