Ignition Control Module: Description and Operation
DESCRIPTION AND OPERATIONIgnition Control Module (ICM):
The Ignition Control Module (ICM) receives crankshaft position and speed information from the Crankshaft Position (CKP) sensor, and desired spark advance information from the Powertrain Control Module (PCM) supplied Spark Output (SPOUT) signal. It uses this information to direct which ignition coil to fire, and controls the turn ON and turn OFF of that ignition coil to achieve the correct dwell and spark advance. The ICM also synthesizes a Profile Ignition Pickup (PIP) signal. The PIP signal is used by the PCM for control strategy. The Ignition Diagnostic Monitor (IDM) signal sends electronic ignition system failure information to the PCM, where the information is stored for use during diagnostic test mode. The IDM also provides the signal to drive the tachometer.