Powertrain, generic · Hybrid propulsion

P0C07 Drive Motor A Phase U-V-W Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0C07 is the high member of the drive motor A phase circuit group: a U, V or W phase line reads higher than it should, most likely through a short to the positive high-voltage rail or a power switch that stays on. Its siblings are P0C05 for an open phase and P0C06 for a phase pulled low. No manufacturer documents P0C07 publicly; among these three, GM uses only P0C05, which watches for missing phase current. CARB requires circuit monitoring of hybrid input and output components. Because a stuck high phase drives uncontrolled current, the inverter normally disables motor A at once. The driver sees a warning lamp and loses some or all electric propulsion until the shorted part is replaced.

Likely causes

Shorted high-side power switch in the motor A inverter
Phase cable shorted to the positive high-voltage path
Faulty gate driver holding a switch on

Symptoms

  • Immediate shutdown of electric drive with warning lamp
  • Reduced performance or engine-only operation

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€200–6,000
Time1–10 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

P0C05P0C06P0C0AP0C01P0BFD

References: law.cornell.edu, gsi.ext.gm.com.