OBD-II code · Powertrain (generic)
P0C4B Hybrid/EV Battery Pack Coolant Pump A Supply Voltage Circuit/Open
The HV battery pack coolant pump A reports a supply voltage circuit/open condition. Battery thermal management may be impaired.
Is it safe to drive with P0C4B?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyOpen in supply wire
- PossibleSupply fuse blown
- Less likelyPin pushed back out of connector body
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 2–7 h
- Emissions test
- Usually unaffected
- Parts involved
- Hv Battery Pack Coolant Pump A, Wiring Harness, Bms
Related codes
- P0C48Hybrid/EV Battery Pack Coolant Pump A Control Circuit Low
- P0C49Hybrid/EV Battery Pack Coolant Pump A Control Circuit High
- P0C4AHybrid/EV Battery Pack Coolant Pump A Control Performance
- P0C4CHybrid/EV Battery Pack Coolant Pump A Supply Voltage Circuit Low
- P0C4DHybrid/EV Battery Pack Coolant Pump A Supply Voltage Circuit High
- P0C4EDrive Motor A Position Exceeded Learning Limit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.