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 Pack's primary circuits.

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.
The Ignition Control Module provides an Ignition Diagnostic Monitor signal which is used by the PCM to detect ignition system failure.
The Ignition Diagnostic Monitor signal also supplies a tachometer signal for the instrument panel gauge.