OBD-II code · Powertrain (generic)
P0B9F Hybrid/EV Battery Voltage Sense U Circuit
The BMS detects a circuit fault on voltage sense channel U of the high-voltage battery. Cell-group voltage measurement is unreliable on this channel.
Is it safe to drive with P0B9F?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelySense circuit failed
- PossibleWiring fault
- 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
- 2–8 h
- Emissions test
- Usually unaffected
- Parts involved
- Hv Battery Voltage Sense U, Wiring Harness, Bms
Related codes
- P0B7CHybrid/EV Battery Voltage Sense N Circuit
- P0B81Hybrid/EV Battery Voltage Sense O Circuit
- P0B86Hybrid/EV Battery Voltage Sense P Circuit
- P0B8BHybrid/EV Battery Voltage Sense Q Circuit
- P0B90Hybrid/EV Battery Voltage Sense R Circuit
- P0B95Hybrid/EV Battery Voltage Sense S Circuit
- P0B9AHybrid/EV Battery Voltage Sense T Circuit
- P0BA4Hybrid/EV Battery Voltage Sense V Circuit
- P0BA9Hybrid/EV Battery Voltage Sense W Circuit
- P0BAEHybrid/EV Battery Voltage Sense X Circuit
- P0BB3Hybrid/EV Battery Voltage Sense Y Circuit
- P0BB8Hybrid/EV Battery Voltage Sense Z Circuit
- P0B9CHybrid/EV Battery Voltage Sense T Circuit Low
- P0B9DHybrid/EV Battery Voltage Sense T Circuit High
- P0B9EHybrid/EV Battery Voltage Sense T Circuit Intermittent/Erratic
- P0BA0Hybrid/EV Battery Voltage Sense U Circuit Range/Performance
- P0BA1Hybrid/EV Battery Voltage Sense U Circuit Low
- P0BA2Hybrid/EV Battery Voltage Sense U Circuit High
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.