OBD-II code · Powertrain (generic)

P0AA6 Hybrid Battery Voltage System Isolation Fault

The BMS isolation monitor detects insulation resistance between HV positive/negative bus and chassis ground below the safe threshold, indicating insulation failure somewhere in the HV system.

Is it safe to drive with P0AA6?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyHV cable insulation damaged
  • PossibleMoisture intrusion in HV component
  • Less likelyAged HV component insulation

Repair at a glance

Difficulty
Shop_only
DIY friendly
Best left to a mechanic
Typical labour
3–14 h
Emissions test
Usually unaffected
Parts involved
Hv Battery, Hv Cabling, Inverter, Charger

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.