Circuit/System Testing
- Turn OFF the ignition.
- Disconnect the ECM C2 harness connector.
- Test the affected IC circuit for the following:
- Short to voltage
- Short to ground
- Open/high resistance
- If a fault is found, repair the circuit as needed.
- Connect the ECM the C2 harness connector.
- Exchange the affected ignition coil/module, with the ignition coil/module of a cylinder that is not affected.
- Start the engine and observe the scan tool.
- If the DTC or the misfire transfers with the suspect ignition coil/module, replace that ignition coil/module assembly.
- If the DTC or the misfire does not transfer with the suspect ignition coil/module, replace the ECM.
IMPORTANT:
A high resistance on any IC circuit can cause a misfire before the DTC sets.