Ignition Control Module
WARNING: This page is about a different car, the 2003 Pontiac Grand Am, 2003 Oldsmobile Alero, 2003 Chevrolet Monte Carlo, and 2003 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
The Ignition Control Module (ICM) is mounted under the ignition coils. The Powertrain Control Module (PCM) uses information from the Ignition Control Module (ICM) and the Camshaft Position (CMP) sensor to determine when an engine misfire is occurring. During cranking, the ICM monitors the 7X Crankshaft Position (CKP) sensor signal. Once the engine starts the ICM determines spark synchronization, by the CMP sensor pulses.