OBD-II code · Powertrain (generic)
P0A91 Drive Motor B Performance
The drive motor B does not deliver the expected torque or efficiency. Phase imbalance, magnet weakness, or bearing wear.
Is it safe to drive with P0A91?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyPhase current imbalance
- PossibleMagnet flux degraded
Symptoms
- EV/hybrid system warning light on
- Reduced motor power or torque
- Possible limp mode or vehicle shutdown
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 3–16 h
- Emissions test
- Usually unaffected
- Parts involved
- Drive Motor B
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.