Powertrain
generic / SAE
P01EA
Engine Coolant Heater A Control Circuit High
Coolant heater A control voltage above expected range. 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 / number1 / EA
Possible causes
- Wiring shorted to battery high
- Connector pins corroded - high contact resistance low
- Supply wire pinched against B+ source low
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 80–600 €
- Estimated time: 0.5–3 h
- Component: coolant heater a
- Component: heater wiring
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012