OBD-II · Engine and powertrain (P)
P0383
Glow plug control module control circuit low
What it means
The glow-plug control module control circuit has a low-level electrical fault. The monitored circuit and detection criteria depend on the vehicle, so this does not automatically identify the command wire from the engine computer.
Symptoms
- harder starting when cold
- rough running and white smoke for the first moments after a cold start
- glow plug light may flash
- possibly no symptoms in warm weather
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | module power-supply or engine/module ground fault |
| 02 | control-circuit wiring or connector fault |
| 03 | failed glow-plug control module |
What to check, step by step
- 01Identify the monitored circuit and full fault details in the vehicle-specific service information.
- 02Check module supply and engine/module grounds under load.
- 03Inspect connectors and test the identified control circuit for opens or shorts.
- 04Replace the module only after supply, grounding and wiring faults have been excluded.