P0C95
Hybrid/EV Battery Temperature Sensor K Circuit High.
- Generic
- Powertrain
- Generic code
- Medium severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- C
- AreaHybrid propulsion
- 95
- FaultThe specific fault in that area
What it means
P0C95 is a generic powertrain code meaning the hybrid or EV battery temperature sensor 'K' circuit is reading high. The battery control unit saw a signal voltage from that sensor above its expected range, which usually points to an open circuit, a short to voltage or a faulty sensor. Which physical sensor 'K' refers to depends on the vehicle and battery pack layout.
Symptoms
- Hybrid or EV system warning light on the dashboard
- Malfunction indicator lamp illuminated
- Reduced power or limp-home mode
- Reduced regenerative braking or limited charging
- Cooling fan for the battery running constantly or not at all
- Reduced electric range or the car refusing to enter ready or charge mode
Possible causes
- Open circuit in the sensor signal or return wire, or a poor connection at the sensor connectorlikely
- Faulty battery temperature sensor (thermistor) reading out of rangelikely
- Corroded, loose or damaged connector terminals at the sensor, battery module or battery control unitpossible
- Short to voltage on the sensor signal wire due to chafed or damaged harnesspossible
- Fault within the battery control unit or battery monitoring modulerare
- Software issue in the battery control unit where the manufacturer has a known calibration updaterare
How to diagnose
- Read all stored and pending codes and freeze frame data, noting battery temperature readings and whether other temperature sensor codes are present
- Check the manufacturer's information to identify which sensor is 'K' on this model and where it sits in the pack
- Compare live data from all battery temperature sensors; a sensor stuck at an extreme value while the others agree points to the circuit or sensor
- Following the manufacturer's high-voltage safety procedure, visually inspect accessible wiring and connectors for damage, moisture, corrosion and pushed-out pins
- Check the sensor resistance against the specification at a known temperature, and compare it with neighbouring sensors
- Test the signal, reference and return wiring for continuity, and for shorts to voltage or ground, with the connector disconnected
- Check for any technical service bulletins or software updates relating to the battery control unit for this model
- Only after the wiring and sensor are proven good, consider testing or replacing the battery control unit
How to fix
- Repair or replace damaged wiring and clean or replace faulty connector terminals
- Replace the faulty battery temperature sensor or sensor harness, as the model allows
- Replace the battery monitoring module or control unit if it is confirmed faulty
- Apply an updated control unit calibration only where the manufacturer lists it as a fix for this fault
- Clear the code after repair and confirm it does not return on a road test
Can I keep driving?
Medium severity
The car may still be driveable, but the system may restrict power or charging to protect the battery, so book it in soon. If a red warning appears, the car loses power or the battery becomes hot or smells, stop and seek recovery.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.