P0351
DTC P0351, P0352, or P0353
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions for an overview of each diagnostic category.
DTC Descriptors
DTC P0351
- Ignition Coil 1 Control Circuit
DTC P0352
- Ignition Coil 2 Control Circuit
DTC P0353
- Ignition Coil 3 Control Circuit
Diagnostic Fault Information
Circuit/System Description
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 engine control module (ECM) 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 companion cylinders 1 and 4. The ignition coil 2 controls spark for companion cylinders 2 and 5. The ignition coil 3 controls spark for companion cylinders 3 and 6.
Conditions for Running the DTC
* The engine is cranking or running.
* The DTCs run continuously when the above condition is met.
Conditions for Setting the DTC
The PCM detects a fault in an ignition coil control circuit for 90 out of 100 engine cycles.
Action Taken When the DTC Sets
DTCs P0351, P0352, P0353 are Type B DTCs.
Conditions for Clearing the MIL/DTC
DTCs P0351, P0352, P0353 are Type B DTCs.
Circuit/System Verification
1. With the engine running, observe the Cylinder 1 through 6 IC Circuit Status parameters with the scan tool. All of the parameters should display OK.
2. With the engine running, observe the Misfire Current counters using the scan tool. The counters should not be incrementing.
Circuit/System Testing
1. With the engine running, observe the applicable Cylinder 1 through 6 IC Circuit Status parameters with the scan tool.
^ If a parameter displays short Gnd/Open, test for an open/high resistance or a short to ground in the affected IC circuit. All wire circuit resistance should measure less than 2 ohms.
^ If a parameter displays short to B+, test for a short to voltage in the affected IC circuit.
2. Connect jumper wires from the harness connector of the ICM to the corresponding terminals of the ICM.
3. Using the jumper wires, exchange the affected IC control circuit with a known good IC control circuit. Also exchange the spark plug wires of the corresponding coils.
4. Start the engine.
Important: An open/high resistance on the low reference circuit to the ICM may cause a misfire.
5. Observe the Misfire Current counters with the scan tool.
^ If the misfire transfers with the suspect IC control circuit, replace the ECM.
^ If the misfire remains with the coil, replace the ICM.
Component Testing
* With positive polarity to the low reference terminal, measure for 9,000-11,000 ohms at 20-23°C (68-74°F) room temperature between each of the ignition coil control terminals and the low reference terminal of the ICM.
^ If the resistance is not within the specified range, replace the ICM.
* Measure for 7,000-15,000 ohms at 20-23°C (68-74°F) room temperature between each pair of coil towers on the ICM.
^ If the resistance is not within the specified range, replace the ICM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Ignition Coil Replacement