FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Ignition Control Module: Description and Operation

DESCRIPTION AND OPERATION
The Ignition Control Module (ICM) with Computer Controlled Dwell (CCD), features powertrain control module controlled ignition coil charge times. The ICM uses the spark output signal to switch the ignition coil primary current OFF and to produce a spark. It then switches ON the coil primary current in time for the ignition coil to charge to a predetermined value before the next spark is scheduled to occur.