Circuit/System Description

WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The ignition system on this engine uses an individual coil/module for each cylinder. The engine control module (ECM) controls the spark event for each cylinder through the eight individual ignition control (IC) circuits. When the ECM commands the IC circuit ON, electrical current will flow through the primary winding of the ignition coil, creating a magnetic field. When a spark event is requested, the ECM will command the IC circuit OFF, interrupting current flow through the primary winding. The magnetic field created by the primary winding will collapse across the secondary coil windings, producing a high voltage across the spark plug electrodes. The ECM uses information from the crankshaft position (CKP) sensor, and the camshaft position (CMP) sensor for sequencing and timing of the spark events. Each ignition coil/module assembly has the following circuits:

Ignition voltage
Ground
Ignition control (IC)
Low reference

If the ECM detects that the IC circuit has an incorrect voltage level, DTC P0351-P0358 will set.