Powertrain
generic / SAE
P0B28
Hybrid/EV Battery B Voltage Unstable
The voltage measurement of HV battery B fluctuates beyond the expected window. Loose connection or unstable cell.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / numberB / 28
Possible causes
- Loose busbar or terminal connection high
- Cell with unstable internal resistance medium
- Pack cell imbalance approaching service threshold low
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 500–5000 €
- Estimated time: 3–16 h
- Component: hv battery b
- Component: bms
- MIL / check engine light
- limp mode possible
Sources
References
sae:J2012