C 3500 Truck 2WD V8-8.1L VIN G (2001)
Ignition Coil: Description and Operation
IGNITION COILS
Ignition Coils
The ignition system on this vehicle features a multiple coil configuration and is known as coil near plug. There are two styles of ignition coil assemblies
(1 ,2). The engine could have either style. The ignition coil mounting bracket is attached to the rocker cover (3).
The 8 ignition coils are individually mounted above each cylinder on the rocker covers, the coils are fired sequentially. There is an Ignition Control (IC)
circuit for each ignition coil. The 8 ignition control circuits are connected to the PCM, the PCM triggers each ignition coil individually and makes all
timing decisions. The ignition coils are supplied with the following circuits:
^
The ignition 1 voltage circuit
^
The ignition control circuit
^
The ground circuit
^
The reference low circuit
The ignition 1 voltage circuits are fused separately for each bank of the engine. The 2 fuses also supply the power for the injectors for that bank of the
engine. Each coil is serviced separately.
This system puts out very high ignition energy for plug firing. Less energy is lost to ignition wire resistance because the ignition wires are much shorter
than in a conventional ignition system.
