Code result
P0AA5
Hybrid/EV Battery Negative Contactor Circuit Stuck Open
High severity
What it means
The HV battery negative contactor is stuck open. HV system cannot establish a complete circuit.
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
Contactor mechanically failed
highOne of the most commonly reported causes for this code — check this first.
Contactor coil burnt out
mediumA plausible cause — test and verify before replacing parts.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Related help
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