P0C42Hybrid/EV Battery Pack Coolant Temperature Sensor A Circuit
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0C42 is the general circuit code for the first coolant temperature sensor in the liquid loop of a hybrid or EV battery, typically placed at the pack inlet. The battery controller uses it to decide when to pump, heat or chill the coolant. Volvo documents P0C4200 in the battery energy control module of the XC90 T8 plug-in hybrid from model year 2016, as either an intermittent or a permanent entry with a possible check engine lamp; according to technical journal TJ 33546, once the current software is verified the entry is simply erased and no parts are needed. GM reports faults of the same sensor more precisely as P0C44 and P0C45. CARB requires the inputs of the battery thermal management to be monitored. P0C43 covers implausible readings, P0CD5 sensor B.
- What you may notice
- Check engine lamp, often without other complaints
- Battery cooling or heating running on substitute values
- Reduced charging or drive power in hot or cold weather
- Likely causes
- LikelyBattery controller software flagging the circuit wrongly (Volvo XC90 T8)
- PossibleCorroded or loose connector or damaged wire at the coolant sensor
- RareFailed coolant temperature sensor A
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €0 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.