P064C
P064C-GLOW PLUG MODULE INTERNAL PERFORMANCE
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
The glow plugs provide a hot spot in the combustion chamber, and are used to aid in cold starting. The Glow Plug Control Module (GPCM) controls the glow plug temperature by regulating the current supplied to the glow plugs. The GPCM communicates with the PCM via the J1939 engine datalink, and the glow plug temperature and operation time is based on engine information supplied by the PCM. The GPCM monitors the status of each glow plug individually, and reports diagnostic failures to the PCM via the J1939 datalink. The glow plug system will be disabled when the fault is set. The PCM will turn OFF the MIL after 3 consecutive ignition cycles that the diagnostic runs and passes.
- When Monitored:
Initially at key on and the Glow Plug Control Module is commanding the Glow Plugs on.
- Set Condition:
The Glow Plug Control Module detects an issue with it's internal circuitry or hardware.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
Diagnostic Test
1. POWERTRAIN CONTROL MODULE CALIBRATION
1. Ignition on, engine not running.
2. With the scan tool, check the PCM for the proper calibration level.
Is the PCM calibration correct and at the latest version?
Yes
- Go To 2
No
- Reprogram the Powertrain Control Module with the latest software version.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
2. ACTIVE DTC
1. Turn the ignition off for at least 10 seconds.
2. Turn the ignition on.
3. With the scan tool, clear DTCs.
4. With the scan tool, navigate to actuator tests and perform the Glow Plug Service Override Test twice without starting the engine.
Did the DTC become active?
Yes
- Replace the Glow Plug Control Module.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.
No
- Perform the INTERMITTENT CONDITION - 6.7L diagnostic procedure. Intermittent Condition Test