P0ACEHybrid/EV Battery Temperature Sensor C Circuit Intermittent/Erratic
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P0ACE flags erratic behaviour of battery temperature sensor C, meaning the reading jumps faster than the heavy battery mass could ever warm or cool. In GM's 2016 and 2019 hybrid tables the controller sums the absolute changes of the sensor value across a 10-sample window taken every 100 ms; a sum above 10 fails the window, and 4 failed windows out of 5 store the code as Type B, two trips. This is the same logic GM uses for sensors A and B. The older two-mode and 2013 programs do not list an erratic code for sensor C. Typical culprits are a loose terminal, a partly broken wire or a connector not fully latched after pack service. Several jumping sensors at once point to the sensing board.
- What you may notice
- Hybrid warning light that appears intermittently
- Sensor C value jumps in live data
- Occasional power limitation
- Likely causes
- LikelyLoose terminal or unlatched connector at sensor C
- PossiblePartly broken sensor wire inside the pack
- RareFault on the battery sensing board affecting several inputs
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €100 – €2,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.