P0AA6 Hybrid/EV Battery Voltage System Isolation Fault

P0AA6 indicates a hybrid or EV battery voltage system isolation fault. The high-voltage battery system has insulation leakage below the expected threshold.

Code status

Needs verification

Not yet verified against SAE J2012_202509 / J2012DA. Treat unverified rows as a lookup aid, not repair authority.

System: Hybrid / EV
Scope: iso-sae-controlled-p0
Standard: SAE J2012 / ISO 15031-6
Source: legacy-import

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not drive or service high-voltage components with an unresolved isolation fault until safety procedures are followed.

Useful checks before replacing parts

Review isolation resistance data, pack voltage, contactor state, humidity or water exposure, freeze-frame data, and related isolation sensor codes.
Inspect high-voltage battery case connectors, service disconnect, orange cables, coolant intrusion, water damage, corrosion, and recently serviced components.
Follow manufacturer isolation test procedures to isolate whether leakage is in the battery, inverter, converter, motor, generator, or wiring.

Related OBD-II codes

These nearby hybrid / ev entries can help compare wording and fault area. They may share the same verification status as the source database.