OBD-II code · Powertrain (generic)
P0A27 Hybrid/EV Battery Power Off Circuit
The hybrid battery power-off control circuit reports a generic fault. Safe disconnection of the HV system cannot be commanded reliably.
Is it safe to drive with P0A27?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyPower-off wiring fault
- PossibleMain contactor 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
- Hybrid Battery Power Off Circuit, Main Contactors, Bms
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.