Code result
P0A91
Drive Motor B Performance
High severity
What it means
The drive motor B does not deliver the expected torque or efficiency. Phase imbalance, magnet weakness, or bearing wear.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Phase current imbalance
highOne of the most commonly reported causes for this code — check this first.
Magnet flux degraded
mediumA plausible cause — test and verify before replacing parts.
Related help
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