Code result
P2C85
Hybrid/EV Battery Voltage External Isolation Fault
High severity
What it means
The hybrid control module detects an isolation fault between the high-voltage battery and the vehicle chassis. Indicates degraded HV insulation.
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
HV cable insulation chafed against chassis
highOne of the most commonly reported causes for this code — check this first.
Moisture in HV connector
mediumA plausible cause — test and verify before replacing parts.
Pack cell imbalance approaching service threshold
lowLess common, but worth ruling out after the more likely causes.
Related help
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