P0AC6Hybrid/EV Battery Temperature Sensor B Circuit Range/Performance
- 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
- P0AC6 is the plausibility test for battery temperature sensor B: its reading is compared with the other pack sensors. GM documents several calibrations. The 2016 and 2019 tables fail it when the sensor differs from the average of the other sensors by more than 25 °C, 50 of 67 samples; the two-mode hybrid tables of 2011 and 2013 use more than 15 °C, 90 of 100 samples; GM's 2013 table 13OBDG05C allows 8.55 °C after more than 6 hours off. All are Type B, two trips. Bulletin 18-NA-342 for the Chevrolet Volt lists P0AC6 among false sensor codes in cold weather and fixes them by reprogramming. Otherwise a drifting sensor or a real local hot spot in a module is likely.
- What you may notice
- Check engine or hybrid warning light
- One sensor reading far off the others in live data
- Battery too cold message on the Volt in mild weather
- Likely causes
- LikelySensor B drifted from its characteristic
- PossibleController software flags the sensor falsely (GM Volt bulletin 18-NA-342)
- PossibleCorroded contact adding resistance in the sensor circuit
- RareReal temperature difference from a weak cell or blocked cooling
- 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: €60 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.