Powertrain, generic · Hybrid propulsion

P0C05 Drive Motor A Phase U-V-W Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

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.

Likely causes

Loose or open three-phase terminal between inverter and motor A
Software fault, cured by update (Jeep TSB 08-144-23)
Internal fault of the motor generator unit or open stator winding
One-off event that does not return after clearing (Volvo TJ 36863)

Symptoms

  • 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

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–5,000
Time0.5–8 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

drive motor a phase uvwdrive motor a inverter

Related codes

P0C06P0C07P0C08P0C01P0BFDP0BE5P0BE9P0BED

References: gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com.