Powertrain
generic / SAE
P037B
Glow Plug/Heater Indicator Control Circuit High
Glow plug indicator drive line stuck high — short to B+. 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.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number3 / 7B
Possible causes
- Short to B+ high
- Connector pins corroded - high contact resistance low
- Supply wire pinched against B+ source low
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
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 40–300 €
- Estimated time: 0.3–1.5 h
- Component: glow plug indicator
- MIL / check engine light
Sources
References
sae:J2012