P0A65: Drive Motor A Phase W Current High

P0A65 reports overcurrent in phase W of drive motor A. It is the third phase code in Hyundai bulletin 17-01-057-1 for the 2017 Ioniq Hybrid, campaign T2J: with an internal coolant leak in the traction motor, P0A65, P0A5F or P0A62 set with Check Engine and hybrid lights, often joined by the isolation fault P0AA6. Reduced power when accelerating and a non-working air conditioner followed. The fix path is the scan tool isolation test, a coolant inspection of the motor and, if confirmed, a new traction motor. In general, a W-phase winding short or a pinched cable has the same effect. Hyundai inverters measure two phases and calculate the third, per a Hyundai patent. P0A64 is the low side, P0A63 the general W code, P0A5F and P0A62 phases U and V.

Symptoms

• Check Engine and hybrid warning lights
• Reduced power when accelerating
• Air conditioning inoperative (Hyundai Ioniq Hybrid)

Most likely causes

• Internal coolant leak in the traction motor (Hyundai Ioniq Hybrid)
• Phase W lead or winding shorted to ground or to another phase
• Inverter power stage fault in phase W
• Current sensor falsely reporting overcurrent

What to check, in order

Start with the simplest. You can tick off each step.

1. Read the codes with a hybrid-compatible scanner and write down the freeze frame data
2. Check the sensor's ground and make sure the signal wire is not receiving voltage from another circuit.
3. Make sure the battery cooling air intake is clean
4. Check the 12 V auxiliary battery, which can also trigger warnings
5. Leave any high-voltage measurements to a specialized repair shop

Good to know

• It can trigger limp mode.
• It affects emissions.

What each character of P0A65 means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• A: Hybrid or air and fuel
• 65: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0A65?

If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

What causes code P0A65?

The most common causes are: internal coolant leak in the traction motor (Hyundai Ioniq Hybrid); phase W lead or winding shorted to ground or to another phase; inverter power stage fault in phase W.

Related codes

• P0A63Drive Motor A Phase W Current
• P0A64Drive Motor A Phase W Current Low
• P0A5FDrive Motor A Phase U Current High
• P0A62Drive Motor A Phase V Current High
• P0AA6Hybrid/EV Battery Voltage System Isolation Fault

Sources

• static.nhtsa.gov: MC 10125162 9999
• patents.google.com: en
• law.cornell.edu: 13 CCR 1968.2

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.