Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provide an overview of each diagnostic category. |
DTC Descriptors
DTC P0351: Ignition Coil 1 Control CircuitDTC P0352: Ignition Coil 2 Control Circuit
DTC P0353: Ignition Coil 3 Control Circuit
DTC P0354: Ignition Coil 4 Control Circuit
DTC P0355: Ignition Coil 5 Control Circuit
DTC P0356: Ignition Coil 6 Control Circuit
DTC P0357: Ignition Coil 7 Control Circuit
DTC P0358: Ignition Coil 8 Control Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Ignition Coil 1 Control Circuit | P0300, P0351 | P0300, P0351 | P0300, P0351 | -- |
Ignition Coil 2 Control Circuit | P0300, P0352 | P0300, P0352 | P0300, P0352 | -- |
Ignition Coil 3 Control Circuit | P0300, P0353 | P0300, P0353 | P0300, P0353 | -- |
Ignition Coil 4 Control Circuit | P0300, P0354 | P0300, P0354 | P0300, P0354 | -- |
Ignition Coil 5 Control Circuit | P0300, P0355 | P0300, P0355 | P0300, P0355 | -- |
Ignition Coil 6 Control Circuit | P0300, P0356 | P0300, P0356 | P0300, P0356 | -- |
Ignition Coil 7 Control Circuit | P0300, P0357 | P0300, P0357 | P0300, P0357 | -- |
Ignition Coil 8 Control Circuit | P0300, P0358 | P0300, P0358 | P0300, P0358 | -- |
Typical Scan Tool Data
Circuit | Normal Range | Short to Ground | Open | Short to Voltage |
|---|---|---|---|---|
Operating Conditions: Engine Running | ||||
Ignition Control (IC) Circuit Status for Cylinders 1-8 | OK or Incomplete | Short to Ground/Open | Short to Ground/Open | Short to B+ |
Circuit/System Description
The ignition system on this engine uses an individual module/coil for each cylinder. The engine control module (ECM) controls the spark event for each cylinder through the 8 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 module/coil assembly has the following electrical circuits attached:
| • | An ignition 1 voltage circuit |
| • | A ground circuit |
| • | An IC circuit |
| • | A low reference circuit |
If the ECM detects that the IC circuit has an incorrect voltage level, DTC P0351-P0358 will set
Conditions for Running the DTC
| • | The engine is running. |
| • | DTC P0351-P0358 runs continuously. |
Conditions for Setting the DTC
The ECM detects the IC circuit is open, grounded, or shorted to voltage for less than 1 second.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
| • | This test procedure requires that the vehicle battery has passed a load test and is completely charged. |
| • | When disconnecting electrical connectors or removing fuses and relays from a fuse block, always inspect the component electrical terminals for corrosion, and the mating electrical terminals for tightness. |
| • | Use the J 35616 for any test that requires probing the underhood fuse block terminals, component wire harness terminals, or the ECM wire harness connector terminals. |
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Scan Tool Reference
Special Tools Required
J 35616 Connector Test Adapter Kit
Circuit/System Verification
- Start and run the engine.
- With a scan tool, monitor all eight ignition control (IC) circuit status parameters in the engine misfire data list.
| ⇒ | All eight IC circuit status parameters should display OK. If the IC circuit status parameter displays, Short to Ground/Open, or Short to B+, continue with the Circuit/System Testing. |
| ⇒ | If the vehicle passes the Circuit/System Verification Test, then operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List. The other option is to refer to Testing for Intermittent Conditions and Poor Connections . |
Circuit/System Testing
- Disconnect the wire harness electrical connector at the ignition module/coil assembly for the cylinder that is identified as misfiring.
- With the key ON, engine OFF, measure for battery positive voltage on the ignition 1 voltage circuit at the ignition module/coil wire harness electrical connector.
- With the key ON, engine OFF, measure the voltage on the IC circuit at the ignition module/coil wire harness electrical connector.
- Disconnect the fuel injector wire harness electrical connector for the misfiring cylinder that you are working on.
- Start and idle the engine. Measure the frequency on the IC circuit at the ignition module/coil wire harness electrical connector, using the DC scale position on the DMM. The frequency should measure between 3-20 Hz.
- With the key ON, engine OFF, probe the low reference circuit with a test lamp that is connected to battery positive voltage.
- Turn OFF the ignition.
- Connect the fuel injector wire harness electrical connector that was previously disconnected.
- Exchange the ignition module/coil of the affected misfiring cylinder with an ignition module/coil assembly of a good cylinder.
- Start and idle the engine.
- Observe the misfire counters for the 2 cylinders that the ignition module/coil assemblies were exchanged on.
| ⇒ | If the voltage measures less than battery positive voltage, then repair an open, high resistance, or short to ground. |
| ⇒ | If the voltage measures more than 1 volt, then test and repair, if necessary the short to voltage in the IC circuit. If the circuit test normal, then replace the ECM. |
| ⇒ | If the frequency measures less than 3 Hz, then test and repair if necessary the IC circuit for an open, high resistance, or short to ground. All wire circuit resistance should measure 2 ohms or less. |
| ⇒ | If the circuit tests normal, then replace the ECM. |
| ⇒ | If the frequency measures more than 20 Hz at idle, then replace the ECM. |
| ⇒ | If the test lamp does not illuminate, then test and repair the low reference circuit for an open or high resistance. All wire circuit resistance should measure 2 ohms or less. |
| ⇒ | If the circuit tests normal, then replace the ECM. |
| ⇒ | If the engine misfire transfers to the new cylinder with the suspected ignition module/coil assembly, then replace that ignition module/coil assembly. |
Repair Instructions
| • | Control Module References for ECM replacement, setup, and programming |
Repair Verification
Operate the vehicle within the condition for running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. If DTC P0351-P0358 sets, then an IC circuit failure still exists.
Important: An ignition system misfire condition can cause the 3-way catalytic converter to overheat under certain driving conditions.
Perform the following test:
- Operate the vehicle at 2,500 RPM, for 5 minutes.
- Operate the vehicle within the Conditions for Running DTCs P0420 or P0430. Refer to DTC P0420 or P0430 . If DTC P0420 or P0430 runs and fails, then diagnosis those DTCs.
- Clear the DTCs with a scan tool.
- Turn OFF the ignition for 1 minute.
