Ignition Control Module: Description and Operation

The electronic ignition system uses an individual ignition coil for each cylinder. There are two separate ignition module assemblies located in the camshaft cover of each cylinder bank. Each ignition module assembly contains an ignition control module and four ignition coils. Each ignition coil connects directly to a spark plug using a boot. This arrangement eliminates the need for secondary ignition wires. The ignition module assemblies receive power from a fused ignition feed. Both ignition module assemblies connect to chassis ground. A Reference Low and four Ignition Control (IC) circuits connect each ignition module assembly to the PCM. The PCM uses the individual IC circuits to control coil sequencing and spark timing for each ignition coil. The IC circuits transmit timing pulses from the PCM to the ignition control module to trigger the ignition coil and fire the spark plug. The PCM controls ignition system sequencing and timing events.

This ignition system produces very high energy to fire the spark plug. There is no energy loss because of ignition wire resistance, or the resistance of the waste spark system. Also, since the firing is sequential, each coil has seven ignition events to saturate as opposed to the three in a waste spark arrangement