P0AA6 code meaning
Hybrid/EV Battery Voltage System Isolation Fault
Powertrain system Generic code P0Axx codes Check engine light
What P0AA6 means
The high-voltage system floats free of the chassis, and an isolation monitor measures the resistance from each HV rail to body ground. P0AA6 sets when that resistance falls below a calibrated limit. GM tables measure with the contactors open and fail below 75,000 ohms (2016) or 213,000 ohms (2019), Type A, one trip; Volt bulletins expect over 275 kOhm after repair, while FMVSS 305 sets 100 ohms per volt DC as the post-crash floor. Documented causes: Volt battery coolant leaks, a chafed HV harness on Ford Aviator/Explorer hybrids, a traction motor coolant leak on the 2017 Ioniq Hybrid; Toyota adds INF codes naming the area. P0AA7 to P0AAB flag the measuring circuit itself. Expect warnings, no charging or a stop-safely message.
P0AA6 at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor2 to 14 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0AA6
- Check engine and hybrid or EV system warning lights
- Vehicle will not charge or will not enter ready mode after restart
- Stop safely now message or reduced power
Common causes of P0AA6
- Most likelyCoolant or moisture inside the battery pack, inverter or drive motor
- PossibleChafed or crushed orange HV cable shorting to the body
- PossibleInsulation breakdown in the electric A/C compressor or a motor winding
- Less likelyElectrolyte leakage or contamination inside the battery sections
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv batteryHv cablingInverterCharger
What each part of P0AA6 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| A | Area: hybrid propulsion. |
| A6 | The exact fault in that area. |
What to do next
- Note P0AA6 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0AA6
What does P0AA6 mean?
P0AA6 means "Hybrid/EV Battery Voltage System Isolation Fault". The high-voltage system floats free of the chassis, and an isolation monitor measures the resistance from each HV rail to body ground. It is a generic code, so it means the same on every make.
Is it safe to drive with P0AA6?
Drive gently and only to a workshop. With P0AA6 the car can go into limp mode (reduced power) to protect itself.
Will P0AA6 fail an emissions test?
P0AA6 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P0AA6 to fix?
Difficulty: workshop only. A typical repair takes 2 to 14 hours of work. This is a job for a workshop.
Will P0AA6 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.