This content was compiled automatically and has not yet been reviewed by a technician. For reference only.
For reference only. Always confirm part numbers and procedures for your specific vehicle.
Fault diagnosis
P0AA6: high-voltage insulation fault with reduced power (2017 IONIQ Hybrid T2J case)
Engine and hybrid warning lights come on, possibly with reduced acceleration power and inoperative air conditioning.
P0AA6: high-voltage insulation fault with reduced power (2017 IONIQ Hybrid T2J case)
Symptoms
- Engine and hybrid warning lights come on, possibly with reduced acceleration power and inoperative air conditioning. [1]
Diagnostic trouble codes
- P0AA6 (generic): Hybrid battery voltage system isolation fault. [1]
Possible causes
- An internal coolant leak in the drive motor of vehicles covered by T2J can trigger this combination of warnings. [1]
Checks
- Have a qualified technician verify campaign applicability and perform the insulation test according to the TSB; if it passes, proceed with coolant leak testing. High-voltage work must follow the manufacturer's safety procedures. [1]
What to do
- Replace the motor according to the manufacturer's procedure only after testing determines that it has failed; complete coolant filling and bleeding, calibration and fault rechecking. [1]
Applicability and limits
- Hyundai Motor America TSB 17-01-057-1; only certain 2017 model year IONIQ Hybrid AE HEV vehicles covered by service campaign T2J. This is not the cause of all P0AA6 occurrences. Do not apply to Chinese brands. No site brand/model dictionary mapping has been made; do not use this to establish vehicle fitment or automatically recommend replacement. Scope: unknown [1]
Related part categories
- Hybrid drive motor [1]
Sources
[Source 1] Hyundai TSB 17-01-057-1: Traction Motor Inspection and Replacement (T2J) — pp.1,3,5–6,10,13; November 2017 (accessed 2026-10-30)
https://static.nhtsa.gov/odi/tsbs/2017/MC-10125162-9999.pdf
Related Academy Articles
Fault diagnosis
Rough idle: electronic EGR valve sticking inspection clues
The engine idles roughly (rough idling) or hesitates during acceleration.
Fault diagnosis
Engine stalls or enters emergency mode: airflow meter inspection clues
The engine stalls or the control unit enters an emergency program, possibly with the engine warning light on.
Fault diagnosis
Charging indicator does not light with ignition on and engine stopped
The ignition is switched on and the engine is not yet running, but the charging/battery indicator does not light.