OBD-II code · Powertrain (generic)
P0C20 Electric/Auxiliary Transmission Fluid Pump Phase U-V-W Circuit/Open
The auxiliary transmission fluid pump phase U-V-W output reports a circuit/open condition.
Is it safe to drive with P0C20?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyOpen phase wire
- PossibleOpen motor winding
- Less likelyPin pushed back out of connector body
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 2–8 h
- Emissions test
- Usually unaffected
- Parts involved
- Aux Trans Pump Phase Uvw, Aux Trans Pump Inverter
Related codes
- P0C1DElectric/Auxiliary Transmission Fluid Pump Control Module Internal Temperature Sensor Circuit Range/Performance
- P0C1EElectric/Auxiliary Transmission Fluid Pump Control Module Internal Temperature Sensor Circuit Low
- P0C1FElectric/Auxiliary Transmission Fluid Pump Control Module Internal Temperature Sensor Circuit High
- P0C21Electric/Auxiliary Transmission Fluid Pump Phase U-V-W Circuit Low
- P0C22Electric/Auxiliary Transmission Fluid Pump Phase U-V-W Circuit High
- P0C23Electric/Auxiliary Transmission Fluid Pump Control Module Circuit/Open
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.