P0AECHybrid/EV Battery Temperature Sensor D 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
- P0AEC flags erratic behaviour of battery temperature sensor D: the reading jumps faster than the heavy battery mass could ever warm or cool. GM documents the method in its 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. GM applies the same logic to sensors A to C. The older two-mode and eAssist tables list no erratic code for sensor D. Typical culprits are a loose terminal, a partly broken wire or a connector not fully latched after pack service. If several sensors jump at once, suspect the sensing board rather than the individual thermistor.
- What you may notice
- Malfunction indicator lamp after two trips, may go out again
- Jumping battery temperature in live data
- Occasional power limitation
- Likely causes
- LikelyLoose terminal or connector not fully latched at sensor D
- PossiblePartly broken or chafed sensor wire
- RareFault on the battery sensing board
- 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.