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P0351



DTC P0351 or P0352

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview)provides an overview of each diagnostic category.

DTC Descriptors
DTC P0351
- Ignition Coil 1 and 4 Control Circuit

DTC P0352
- Ignition Coil 2 and 3 Control Circuit


Diagnostic Fault Information





Circuit/System Description

Ignition 1 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. The ignition coils consist of the following circuits:

* The ignition 1 voltage
* The IC 1 and 4 control
* The IC 2 and 3 control

Conditions for Running the DTC

* The engine is running.
* The DTCs run continuously once the above condition is met.

Conditions for Setting the DTC

The ECM detects an open or short to ground or voltage on the IC circuit.

Action Taken When the DTC Sets

* DTC P0351 and P0352 are Type B DTCs.
* The ECM commands open loop fuel control.

Conditions for Clearing the DTC

DTC P0351 and P0352 are Type B DTCs.

Diagnostic Aids

The mounting bracket for the coil assembly provides the ground for the ignition coils. Ensure the mounting bolts are torqued to the correct specification. Refer to Fastener Tightening Specifications (Specifications).

Reference Information
Schematic Reference

Engine Controls Schematics (MR140 w/o Throttle Actuator Control) (Electrical Diagrams)Engine Controls Schematics (MT34 w/Throttle Actuator Control) (Electrical Diagrams)Engine Controls Schematics (Hatchback) (Electrical Diagrams)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Control Module References (Programming and Relearning)for scan tool information

Circuit/System Verification

1. Engine running, observe the DTC information with a scan tool. DTC P0351 and P0352 should not set.
2. 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. Ignition ON, verify that a test lamp illuminates between the ignition 1 voltage circuit terminal B and ground.

If the test lamp does not illuminate, test the ignition 1 voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition 1 voltage circuit fuse is open, test all components connected to the ignition 1 voltage circuit and replace as necessary.

Important: Set the DMM to the AC Hertz scale for this test.


3. Connect a DMM between the appropriate ignition control circuit and ground.

* Ignition coil 1 and 4 control terminal C
* Ignition coil 2 and 3 control terminal A

4. Engine cranking, test for more than 2 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.

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

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Ignition Coil Replacement (Service and Repair)
* Control Module References (Programming and Relearning)for ECM replacement, setup, and programming