OBD-II code · Powertrain (generic, extended)
P2B28 Hybrid/EV Battery Pack Coolant Pump A Performance
The hybrid control module detects that battery pack coolant pump A does not produce the expected flow for the commanded duty. Battery thermal management may be impaired.
Is it safe to drive with P2B28?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyPump output degraded with age
- PossibleAir pocket in coolant loop
- Less likelyPack cell imbalance approaching service threshold
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
- 2–6 h
- Emissions test
- Usually unaffected
- Parts involved
- Hybrid Battery Coolant Pump A, Battery Pack, Hybrid Control Module
Related codes
- P2B25Hybrid/EV Electronics Coolant Temperature Sensor C Range/Performance
- P2B26Hybrid/EV Electronics Coolant Temperature Sensor C Circuit Low
- P2B27Hybrid/EV Electronics Coolant Temperature Sensor C Circuit High
- P2B29Hybrid/EV Battery Pack Coolant Pump A Overspeed - Dry Run
- P2B2AHybrid/EV Electronics Coolant Pump A Overspeed - Dry Run
- P2B2BEngine Coolant Temperature Sensor 5 Circuit
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.