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Ignition Control Module: Description and Operation


PURPOSE
To provide the Powertrain Control Module (PCM) with a means of controlling the ignition timing by regulating the ignition coil's primary circuit.

OPERATION
The Ignition Control Module receives a control signal from the Powertrain Control Module Spark Output (SPOUT) circuit. From this signal the module determines the proper ignition coil saturation (On time) and timing, thereby controlling the ignition timing for optimum vehicle performance.