Powertrain, generic · Hybrid propulsion

P0C0C Drive Motor A Inverter Power Supply Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P0C0C reports that the supply voltage of the motor A inverter is present but too low, while P0C0B covers a lost or open supply and P0C0D a supply that is too high. Which supply is meant depends on the maker: GM ties its sibling P0C0B to the gate-drive supply of the IGBTs, Mercedes to the high-voltage feed. Audi documents P0C0C on the 2025 and 2026 A6 and Q6 e-tron family: stored in the electric drive modules together with P0E8D, it comes with a red high-voltage fault warning to stop safely, and the bulletin calls for replacing the affected front or rear power electronics. CARB requires circuit monitoring of hybrid components. Without a stable supply the inverter cannot switch, so drive power is cut.

Likely causes

Internal fault of the drive power electronics (Audi TSB 2081725)
Weak 12 V supply, poor ground or high-resistance connector at the inverter
Weak 12 V battery or DC/DC converter output

Symptoms

  • Red high-voltage system warning asking to stop safely
  • Loss of drive power or vehicle will not get ready to drive

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€100–7,000
Time0.5–6 h

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

Parts involved

drive motor a inverterwiring harnesshybrid control module

Related codes

P0C0BP0C0DP0C0FP0A78P0E8D

References: static.nhtsa.gov, law.cornell.edu, gsi.ext.gm.com.