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Ignition Control Module: Description and Operation

Electronic Distributorless Ignition System (EDIS) Module:





The Ignition Control Module (ICM) is a microprocessor-based device with coil drivers which make decisions about spark timing and coil firing. The module turns the coils ON and OFF at the correct time and in the proper sequence based on information from the Crankshaft Position (CKP) sensor and a pulse-width modulated Spark Output (SPOUT) signal generated from the Powertrain Control Module (PCM). The module receives CKP and SPOUT signals and produces Profile Ignition Pickup (PIP) and Ignition Diagnostic Monitor (IDM) output signals which are sent to the PCM.