For 1990-2009 cars

### 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 provides 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
DTC P0354: Ignition Coil 4 Control Circuit
DTC P0355: Ignition Coil 5 Control Circuit

### Diagnostic Fault Information

Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance
--- | --- | --- | --- | --- | ---
Ignition Coil 1 Control Circuit | P0351 | P0351 | P0351 | P0351 | P0351
Ignition Coil 2 Control Circuit | P0352 | P0352 | P0352 | P0352 | P0352
Ignition Coil 3 Control Circuit | P0353 | P0353 | P0353 | P0353 | P0353
Ignition Coil 4 Control Circuit | P0354 | P0354 | P0354 | P0354 | P0354
Ignition Coil 5 Control Circuit | P0355 | P0355 | P0355 | P0355 | P0355

### Circuit/System Description

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. The ECM monitors each IC circuit for improper voltage levels. Each ignition coil/module has the following circuits:

• | Ignition voltage

• | Ground

• | IC

• | Low reference

### Conditions for Running the DTC

• | The engine is running.

• | DTCs P0351-P0355 run continuously when the above condition is met.

### Conditions for Setting the DTC

The ECM detects an open, short to ground, or a short to voltage on the IC circuit or the ignition coil/module for less than 1 second.

### Action Taken When the DTC Sets

DTCs P0351-P0355 are Type B DTCs.

### Conditions for Clearing the MIL/DTC

DTCs P0351-P0355 are Type B DTCs.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

• | Start and idle the engine.

• | Observe the scan tool Misfire Current Cyl. parameters. This will indicate the affected ignition coil/modules, and if the condition is current.

• | 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.

### Circuit/System Testing

1. Turn OFF the ignition.
2. Disconnect the ECM.
3. Test the affected IC circuit terminal B for an open, a high resistance, a short to ground and for a short to voltage.

⇒ | If a fault is found, repair the circuit as needed.

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.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Ignition Coil Replacement

• | Control Module References for ECM replacement, setup, and programming