P0C05Drive Motor A Phase U-V-W Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0C05 detects an open or missing phase between the inverter and drive motor A. GM checks each phase as the rotor passes its axis: if the peak phase axis current stays below 9 A while at least 23 A is commanded, with the rotor within 30 degrees of that axis and over 35 V on the inverter, about 200 failed samples set the code. It is Type A, one trip, on the Volt and two-mode trucks and Type B, two trips, on eAssist. Jeep lists it on the 2018/19 Wrangler eTorque with P0C01, curing it by software or a new motor generator unit. Volvo uses it in the rear axle inverter of 2020 to 2022 PHEVs and advises clearing it and test-driving before replacing parts. Expect reduced electric power.
- What you may notice
- Propulsion system performance message or warning lamp
- Reduced electric drive power
- Loss of 12 V charging or noise from the motor generator on mild hybrids
- Likely causes
- LikelyLoose or open three-phase terminal between inverter and motor A
- PossibleSoftware fault, cured by update (Jeep TSB 08-144-23)
- PossibleInternal fault of the motor generator unit or open stator winding
- RareOne-off event that does not return after clearing (Volvo TJ 36863)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €5,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.