Circuit Description
WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
There are 3 dual-tower ignition coils integrated with the ignition control module (ICM). The ICM contains coil driver circuits that operate the 3 coils. The ICM wiring includes the following circuits:
- An ignition 1 voltage circuit
- A ground circuit
- An ignition coil 1 control circuit
- An ignition coil 2 control circuit
- An ignition coil 3 control circuit
- A low reference circuit
The powertrain control module (PCM) controls each ignition coil by transmitting timing pulses to the ICM on each of the ignition coil control circuits to enable properly timed spark events. The ignition coil 1 controls spark for cylinders 1 and 4. The ignition coil 2 controls spark for cylinders 2 and 5. The ignition coil 3 controls spark for cylinders 3 and 6.
If the PCM detects an incorrect voltage on any of the ignition coil control circuits, the corresponding DTC sets.