P2B25Hybrid/EV Electronics Coolant Temperature Sensor C Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2B25 is the plausibility code for the third electronics coolant sensor. The signal is electrically sound, but its value cannot be right, for example because sensor C still reads cold while sensors A and B in the same loop have long warmed up, or because it jumps by an amount the coolant could not follow. No manufacturer publishes a set condition for P2B25. NTN-SNR describes it as a deviation or malfunction of the sensor C signal, and CARB asks for rationality checks on inverter thermal management inputs. GM's after-soak comparison for sensor A (P0CEF) illustrates the method. A sensor C that sits near a component with its own heat, such as the charger, can also mislead the test if the pump has stopped or the loop holds air. Electrical faults of sensor C go to P2B26 and P2B27.
- What you may notice
- Fault code set after a cold start or a long drive
- Cooling system reacting inconsistently
- Possible limitation of charging power
- Likely causes
- LikelySensor C reading drifted away from the true temperature
- PossibleAir in the loop or a weak pump leaving sensor C without flow
- PossibleCorrosion in the sensor C connector
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €40 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.