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Ignition Control Module: Description and Operation

Ignition Coil/Module:






DESCRIPTION
The ignition coil/ignition coil module provides spark to the distributor, timed by signals from the PCM Power (B+) for the ignition coil primary circuit and ignition coil module is supplied by the ignition switch. The PCM combines the camshaft position information supplied by the distributor with other system parameters and calculates the required spark advance and coil dwell. The PCM signals the ignition coil module, which turns "ON" the primary current to the ignition coil by grounding the primary circuit, and then ignition coil by grounding the primary circuit, and then turns it "OFF" by removing the ground. When the primary current flow stops, high voltage induced in the ignition coil secondary winding becomes the spark voltage for the spark plug. The spark voltage is delivered to the distributor through the coil output (secondary) wire, and then directed to the proper spark plug connector by the distributor rotor.