P064C

DTC P064C

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 Descriptor

DTC P064C
- Glow Plug Module Control Performance

Diagnostic Fault Information






Typical Scan Tool Data






Circuit/System Description

The glow plug control module (GPCM) has the ability to perform internal diagnostics for voltage and output state of the glow plugs. The GPCM will send a message to the engine control module (ECM) to set this DTC.

Conditions for Running the DTC

* The ignition is ON.
* DTC P064C runs continuously.

Conditions for Setting the DTC

The GPCM detects a variation between the main battery supply to the GPCM and battery supply to the ECM, or an internal condition for 3 second.

Action Taken When the DTC Sets

DTC P064C is a Type B DTC.

Conditions for Clearing the DTC

DTC P064C is a Type B DTC.

Circuit/System Verification

1. If you cannot duplicate the conditions, Refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics
2. Engine running, observe the DTC information with a scan tool. DTC P064C should not set.
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame Records data.

Circuit/System Testing

Monitor the GPCM Data Display Ignition 1 Signal parameter for battery voltage with a scan tool.

If the Ignition 1 Signal parameter is not battery voltage, test the battery positive voltage circuit to the glow plug control module for an open, or short to ground. If the circuits test normal replace the GPCM.
If the Ignition 1 Signal parameter is battery voltage, replace the GPCM.

Repair Instructions

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

Control Module References for GPCM replacement, setup, and programming Programming and Relearning