The ignition system uses individual ignition coil/module assemblies for each cylinder. The engine control module (ECM) controls the individual coils by transmitting timing pulses on the ignition control (IC) circuit of each ignition coil/module to enable a spark event. When the engine is running the ECM monitors each IC circuit for improper voltage levels. Each ignition coil/module has the following circuits:

The ECM detects an open in the circuit or the ignition coil/module for greater than 4 seconds continuously or 50 seconds cumulative.

DTCs P0351, P0352, P0353, P0354 are Type B DTCs.

DTCs P0351, P0352, P0353, P0354 are Type B DTCs.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Start and idle the engine.
2. Observe the scan tool Misfire Current Cylinder parameters. The counters should not be incrementing.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

1. Ignition OFF, disconnect the harness connector at the affected ignition coil/module.
2. Ignition OFF for 90 seconds, disconnect the X1 harness connector at the ECM.
3. Test for less than 5.0 ohms between the ignition coil/module IC circuit terminal 3:

•	IC 1 circuit: terminal 55 X1

•	IC 2 circuit: terminal 80 X1

•	IC 3 circuit: terminal 79 X1

•	IC 4 circuit: terminal 56 X1

⇒	If greater than the specified range, test the IC circuit for an open/high resistance.

4. Connect the ECM.
5. Exchange the affected ignition coil/module with the ignition/coil module of a good cylinder.
6. Start the engine and observe the scan tool.

⇒	If the DTC or the misfire transfers with the suspect ignition/coil module, replace as needed.

⇒	If the DTC or the misfire does not transfer with the suspect ignition/coil module, replace the ECM.

If the customer concern was a flashing MIL, then perform the following procedure:

1. Install any components that have been removed or replaced during diagnosis.
2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.
3. Clear the DTCs.
4. Turn OFF the ignition for 60 seconds.
5. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.
6. To verify that the performance of the catalytic converter has not been affected by the condition that set this DTC, perform the Repair Verification for DTC P0420. Refer to DTC P0420.