OBD-II code · Powertrain (generic)
P0383 Glow Plug Control Module 1 Control Circuit Low
The drive line from the PCM to glow plug control module 1 is stuck low — short to ground. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
Is it safe to drive with P0383?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyShort to ground
- Less likelyConnector pins corroded - high contact resistance
- Less likelyHarness chafing through insulation
Symptoms
- Glow plug warning light on (often orange coil symbol)
- Hard cold start or no start in cold weather
- White smoke from exhaust during warm-up
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.5–2.5 h
- Emissions test
- Likely to fail
- Parts involved
- Glow Plug Control Module
Related codes
- P06F7Glow Plug Control Module 2 Control Circuit Low
- P0380Glow Plug/Heater Circuit "A" Malfunction
- P0381Glow Plug/Heater Indicator Circuit Malfunction
- P0382Glow Plug/Heater Circuit B
- P0384Glow Plug Control Module 1 Control Circuit High
- P0385Crankshaft Position Sensor B Circuit
- P0386Crankshaft Position Sensor B Circuit Range/Performance
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.