Powertrain
generic / SAE
P01F9
Engine Coolant Heater B Control Circuit Driver Current/Temperature Too High
Driver stage of coolant heater A reports overcurrent or overtemperature. Likely short or thermal shutdown.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number1 / F9
Possible causes
- Short circuit in heater wiring or element high
Symptoms
- Check engine light on
- Cooling fan runs constantly or not at all
- Cabin heater weak or excessively hot
- Possible long warm-up time or hard cold start
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 100–700 €
- Estimated time: 0.5–3 h
- Component: coolant heater b
- Component: heater driver
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012