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

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
ignition Voltage | 1 | 2 | -- | --
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 | --

1. The Engine Cranks but Does Not Run and opens the fuse that supplies voltage to the ignition coils.
2. The Engine Cranks but Does Not Run.

### Circuit/System Description

ignition voltage is supplied to the ignition coil. The engine control module (ECM) provides a ground for the ignition coil (IC) control circuits. When the ECM removes the ground path of the ignition primary coil, the magnetic field produced by the coil collapses. The collapsing magnetic field produces a voltage in the secondary coil which ignites the spark plugs. The sequencing and timing are controlled by the ECM.

### Conditions for Running the DTC

• | The engine is running.

• | The ignition voltage is greater than 6 volts.

• | The DTCs run continuously once the above condition is met.

### Conditions for Setting the DTC

The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 5 seconds.

### Action Taken When the DTC Sets

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

### Conditions for Clearing the DTC

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

### Diagnostic Aids

• | Inspect the ignition coils for aftermarket devices. An aftermarket device connected to the ignition coil circuits, may cause this DTC to set.

• | The Hold indicator flashes when there is an engine misfire.

• | If the condition is intermittent, moving the related harnesses and connectors, with the engine operating, while monitoring the appropriate scan tool Misfire Current Cylinder parameter may help to isolate the condition.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Electronic Ignition (EI) System Description

#### 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

1. Engine running, raise the engine speed to 3,000 RPM, while observing the following control circuit status parameters for the appropriate cylinder:

• | IC Ckt Short Gnd Test Status

• | IC Ckt Open Test Status

• | IC Ckt Short Volts Test Status

• | Each parameter should display OK or Not Run.

2. Engine idling, raise the engine speed to 3,000 RPM, observe the DTC information with a scan tool. DTC P0351, P0352, P0353, or P0354 should not set.
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.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the ignition coil.
2. Test for less than 5 Ω between the ground circuit terminal B and ground.

⇒ | If greater than the specified range, repair the ground circuit for an open/high resistance.

3. Ignition OFF for 1 minute, test for less than 5 Ω between the low reference circuit terminal C and ground.

⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

4. Ignition ON, verify that a test lamp illuminates between the ignition voltage circuit terminal A and ground.

⇒ | If the test lamp does not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition voltage circuit fuse is open, test all components connected to the ignition voltage circuit and replace as necessary.

Note: Set the DMM to the DC Hertz scale for this test.

5. Connect a DMM between the appropriate ignition control circuit listed below and ground.

• | Ignition coil 1 control terminal D

• | Ignition coil 2 control terminal E

• | Ignition coil 3 control terminal F

• | Ignition coil 4 control terminal G

6. Engine cranking, test for greater than 1.5 hertz between the appropriate ignition control circuit and ground.

⇒ | If less than the specified range, test the ignition control circuit for a short to voltage, short to ground, or an open/high resistance. If the circuit tests normal, replace the ECM.

7. If all circuits test normal, test or replace the ignition coil.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Ignition Coil Replacement

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