P0C12 code meaning
Drive Motor A Inverter Phase V Over Temperature
Powertrain system Generic code P0Cxx codes Check engine light
What P0C12 means
P0C12 sets when the inverter for motor A measures an excessive temperature at phase V while its sensor itself is plausible. In GM's 2011 Volt table that is PIM sensor C above 98 °C; the two-mode trucks of 2012 use 88 °C with an 85 °C reset, the 2016 Volt 126 °C for 1.2 s out of 2 s and the 2016 ELR 102.5 °C, all Type A, one trip. The sensor circuit codes of that thermistor, such as P0BD1 and P0BD2, have their own numbers and must be ruled out first. P0C11 and P0C13 are phases U and W, P0C15 is phase V on motor B. GM bulletin PIC6303A lists these overheat codes as a sign of insufficient cooling. Power is reduced while the inverter is hot.
P0C12 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0C12
- Malfunction indicator lamp after one drive
- Propulsion power reduced, especially under load or in hot weather
- Hybrid system overheat or service message
Common causes of P0C12
- Most likelyLow coolant level or trapped air in the inverter cooling loop
- Most likelyInoperative electric coolant pump of the power electronics
- PossibleBlocked low-temperature radiator or failed cooling fan
- Less likelyDegraded thermal contact or failing power stage inside the inverter
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Drive motor a inverter phase v
What each part of P0C12 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| C | Area: hybrid propulsion. |
| 12 | The exact fault in that area. |
What to do next
- Note P0C12 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0C12
What does P0C12 mean?
P0C12 means "Drive Motor A Inverter Phase V Over Temperature". P0C12 sets when the inverter for motor A measures an excessive temperature at phase V while its sensor itself is plausible. It is a generic code, so it means the same on every make.
Is it safe to drive with P0C12?
Drive gently and only to a workshop. With P0C12 the car can go into limp mode (reduced power) to protect itself.
Will P0C12 fail an emissions test?
Yes, it can. P0C12 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0C12 to fix?
Difficulty: hard. A typical repair takes 0.5 to 5 hours of work. This is a job for a workshop.
Will P0C12 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.