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 PerformanceDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Battery Positive Voltage | P064C | P064C | -- | -- |
Ignition 1 Voltage | P064C | P064C | -- | -- |
Ignition 0 Voltage | P064C | P064C | -- | -- |
Typical Scan Tool Data
Circuit | Normal Range | Short to Ground | Open | Short to Voltage |
|---|---|---|---|---|
Operating Conditions: Ignition ON | ||||
Battery Positive Voltage | Battery Voltage | 0 Volts | 0 Volts | -- |
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.
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Verification
- If you cannot duplicate the conditions, refer to Testing for Intermittent Conditions and Poor Connections .
- Engine running, observe the DTC information with a scan tool. DTC P064C should not set.
- 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/Failure Records data.
Circuit/System Testing
- Ignition ON, verify the scan tool GPCM Ignition 1 Signal parameter is battery voltage.
- Ignition OFF, disconnect the X2 harness connector at the GPCM.
- Ignition ON, verify that a test lamp illuminates between the ignition 1 voltage circuit and ground.
- Ignition ON, verify that a test lamp illuminates between the ignition 0 voltage circuit and ground.
- If all circuits test normal, replace the GPCM.
| ⇒ | 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 circuit tests normal, replace the GPCM. |
| ⇒ | 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, replace the GPCM. |
| ⇒ | If the test lamp does not illuminate, test the ignition 0 voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the GPCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for GPCM replacement, setup, and programming
