P0C82
Hybrid/EV Battery Temperature Sensor H Circuit Range/Performance.
- Generic
- Powertrain
- Generic code
- Medium severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- C
- AreaHybrid propulsion
- 82
- FaultThe specific fault in that area
What it means
P0C82 means the hybrid or EV control unit has judged the signal from traction battery temperature sensor 'H' to be implausible or out of the expected range. This is a range/performance fault, so the reading is not necessarily an open or short circuit. It is typically flagged when the value does not agree with neighbouring battery temperature sensors, does not change as expected, or is stuck. Which physical sensor is 'H' depends on the vehicle, so check the manufacturer's data.
Symptoms
- Hybrid or EV system warning light, or malfunction indicator lamp, on
- Reduced power or limited charging and regeneration
- Battery cooling fan running louder or more often than normal
- Reduced electric range or the engine running more often on a hybrid
- Slower or restricted rapid charging
- Other battery temperature or battery performance codes stored alongside
Possible causes
- Faulty or drifting battery temperature sensor Hlikely
- Damaged wiring, poor connection or corrosion in the sensor circuit or battery module connectorlikely
- Real temperature imbalance in the battery pack from a cooling fault, such as a blocked intake, failed fan or coolant circuit problempossible
- Fault in the battery monitoring unit or its internal sensing circuitpossible
- Sensor poorly attached to or displaced from its module, giving false readingspossible
- Outdated control unit software where the manufacturer has issued a revision for this faultrare
How to diagnose
- Read all stored codes and freeze frame data, and note whether other battery temperature or cooling codes are present.
- Check for manufacturer service bulletins or software updates for this code on the specific model.
- Visually inspect the battery cooling air intake, ducts and filter for blockage or damage, and check that the cooling fan runs.
- Compare live data from all battery temperature sensors after the car has cooled; sensor H should be close to the others, and all should be near ambient.
- Watch the sensor H reading as the pack warms or cools; look for a stuck, jumping or flat reading.
- Have a qualified high-voltage technician isolate the system following the manufacturer's procedure, then inspect the connectors and wiring for damage, moisture or corrosion.
- Measure sensor resistance and circuit voltage against the manufacturer's specification, and check the wiring for continuity and shorts.
- If the sensor and wiring are good, test the monitoring unit and cooling system operation as per the manufacturer's procedure.
How to fix
- Replace the faulty temperature sensor or sensor harness section.
- Repair or replace damaged wiring and clean or replace corroded connectors.
- Clear blocked cooling ducts or filters, and repair or replace the failed fan or cooling system parts.
- Refit or secure the sensor correctly in its module position.
- Replace or repair the battery monitoring unit if it is confirmed faulty.
- Update the control unit software if the manufacturer lists it as a fix for this fault.
Can I keep driving?
The car can usually be driven for a short time, but power and charging may be limited and the battery may not be protected as well as normal. Avoid long journeys, heavy loads and hot conditions, and have it checked soon, because it is a high-voltage system.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.