P0AA6 — Hybrid/EV Battery Voltage System Isolation Fault

P0AA6: Hybrid/EV Battery Voltage System Isolation Fault — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Hybrid/EV Battery Voltage System Isolation Fault. Basic catalogue definition; diagnostic details have not yet been reviewed.

Affected system: Powertrain

Symptoms

  • A hybrid-system or high-voltage warning can appear.
  • Electric drive or charging may be unavailable, and the vehicle may refuse to enter its ready-to-drive state.

Possible causes

  • Moisture or damage inside the high-voltage battery may reduce insulation from the vehicle chassis.
  • Damaged high-voltage cables, connectors or components such as the inverter or electric A/C compressor can also contribute to an isolation fault.

What to check

  • Read associated hybrid-system fault codes and manufacturer-specific subcodes to help identify the affected section.
  • Do not touch orange high-voltage cables or open the battery enclosure; have a high-voltage-qualified technician check for moisture, damaged insulation and isolation resistance following the exact vehicle's safety and service procedures.

Also written as: P0AA6-00, P0AA600, POAA6 (some scan tools add the fault-type byte, e.g. -00).