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Home >> Chevrolet >> 2005 >> Uplander Base, Van Passenger Extended >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - 3.5L - Introduction (2 Of 2) >> Description and Operation >> Electronic Ignition (EI) System Description >> Ignition Control Module (ICM)/Coils
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Ignition Control Module (ICM)/Coils

There are 3 dual-tower ignition coils mounted to the ignition control module (ICM). The ICM contains coil driver circuits that command the coils to operate. The ICM has the following circuits:

The powertrain control module (PCM) controls each dual-tower ignition coil by transmitting timing pulses on the IC control circuit of the ICM for the proper coil to enable a spark event.

The spark plugs are connected to each coil tower by spark plug wires. The spark plug wires conduct the spark energy from the coil to the spark plug. The spark plug electrode is tipped with platinum for long wear and higher efficiency.