P0ACCHybrid/EV Battery Temperature Sensor C Circuit Low
- 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
- P0ACC sets when the signal of battery temperature sensor C drops below the valid voltage window. For the NTC sensors GM uses, that equals an impossibly hot reading, most often caused by a short to ground in the pack wiring. GM's thresholds for sensor C mirror those for B: above 160 °C in 8 of 10 samples in the 2016 and 2019 tables, above 95 °C in 30 of 40 in the two-mode tables of 2011 and 2013, and below 0.3 V, about 90 °C, in 7 of 10 in the 2013 table 13OBDG05C; always Type B, two trips. Bulletin 18-NA-342 lists P0ACC for the Chevrolet Volt and prescribes a software update first. After that, inspect the sensor C wiring and the sensing board for chafing or moisture.
- What you may notice
- Check engine or hybrid warning light
- Sensor C shows an implausibly high temperature
- Reduced charging and electric drive power
- Likely causes
- LikelySensor C signal shorted to ground
- PossibleThermistor shorted internally
- RareController software setting the code falsely (Volt bulletin 18-NA-342)
- RareMoisture at the sensing board connector
- 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.