P0C11 is a protective code: the temperature sensor at phase U of the motor A inverter reads a valid but excessive value. GM uses it across its hybrids. The 2011 Volt reads PIM sensor A against 98 °C, the 2012 two-mode trucks against 88 °C with a reset at 85 °C, both Type A; the 2016 Volt sets it above 126 °C for 1.2 s within 2 s, the 2019 table above 128 °C, Type A, one trip. On eAssist the single inverter code P0C11 sets above 118.2 °C as Type B, two trips. Sensor faults such as P0AEE block it. Phase V and W are P0C12 and P0C13. GM advises finding the cause of poor cooling. The inverter cuts power to protect itself.
High severity. Can I keep driving?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.
Symptoms
- Malfunction indicator lamp, often with a hybrid system overheat message
- Reduced propulsion power until the inverter cools down
- Electric drive unavailable, engine runs continuously
Most likely causes
- Low coolant level or air in the power electronics cooling loop
- Failed or weak electric coolant pump of the inverter loop
- Clogged power electronics radiator or inoperative cooling fan
- Sustained heavy load such as towing uphill in high ambient heat
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: hard
- It can trigger limp mode.
- It affects emissions.
What each character of P0C11 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- C: Subsystem depends on the code range
- 11: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0C11?
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 P0C11?
The most common causes are: low coolant level or air in the power electronics cooling loop; failed or weak electric coolant pump of the inverter loop; clogged power electronics radiator or inoperative cooling fan.
Related codes
- P0C12Drive Motor A Inverter Phase V Over Temperature
- P0C13Drive Motor A Inverter Phase W Over Temperature
- P0C14Drive Motor B Inverter Phase U Over Temperature
- P0AEDDrive Motor Inverter Temperature Sensor A Circuit
- P0AEEDrive Motor Inverter Temperature Sensor A Circuit Range/Performance
- P0A3CDrive Motor A Inverter Over Temperature
- P0A93Inverter A Cooling System Performance
Sources
- gsi.ext.gm.com: 11OBDG01 HYBRID Diagnostics
- gsi.ext.gm.com: 12OBDG06 Hybrid Diagnostics
- gsi.ext.gm.com: 13OBDG05C Hybrid Diagnostics
- gsi.ext.gm.com: 16OBDG01 Hybrid Diagnostics
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.