P0514
Battery Temperature Sensor Circuit Range/Performance.
- Generic
- Powertrain
- Generic code
- Low severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 5
- AreaVehicle speed, idle control and auxiliary inputs
- 14
- FaultThe specific fault in that area
What it means
P0514 means the powertrain control module has judged the battery temperature sensor signal to be implausible or out of its expected range. It usually sets when the reported battery temperature does not agree with other temperature data, such as intake air or coolant temperature after a long cold soak, or when the signal is stuck or changes unrealistically. The sensor is often built into the battery or a battery current sensor, and on some vehicles it helps control charging voltage.
Symptoms
- Engine management light on
- Battery or charging warning light on some models
- Battery undercharged or repeatedly flat
- Battery overcharged or electrolyte loss in hot conditions
- Stop-start system disabled on vehicles that have it
- Slow or weak cranking in cold weather
Possible causes
- Damaged, corroded or loose wiring or connector at the battery temperature sensorlikely
- Faulty battery temperature sensor, or a sensor integrated into the battery negative lead or current sensor modulelikely
- Poor battery terminal connections or corrosion affecting sensor signal or reference voltagepossible
- Sensor fitted in a location with abnormal heat, for example near the exhaust or a damaged heat shield, causing readings that disagree with other temperaturespossible
- Weak or failing battery causing unstable supply voltage and unreliable readingspossible
- Fault in the powertrain control module sensor input circuitrare
How to diagnose
- Read all stored and pending codes and note the freeze frame data, including battery voltage and temperature readings.
- Check the live battery temperature reading against intake air and coolant temperature after the car has cooled overnight; they should be similar.
- Inspect the sensor, its wiring and connector for chafing, heat damage, water ingress and corrosion.
- Check the battery terminals and earth leads for tightness and corrosion, and look for damage around the battery sensor or current sensor.
- Test the battery state of health and the charging system output to rule out a battery or alternator problem.
- Check the sensor circuit for open circuit, short to earth or short to voltage against the manufacturer wiring diagram, and test the reference voltage and signal at the sensor.
- Compare sensor resistance with the manufacturer temperature specification, noting that the exact procedure and sensor location depend on the model and engine.
- If the sensor and wiring are sound, check for a relevant software update or calibration, and then consider the control module.
How to fix
- Repair or replace damaged wiring and clean or renew corroded connectors.
- Replace the faulty battery temperature sensor or the battery sensor assembly it is part of.
- Clean and tighten battery terminals and earth connections, and replace damaged leads.
- Repair or refit any missing heat shielding, or relocate the sensor to the correct position.
- Replace a weak battery, then fully charge and retest, and register the new battery if the vehicle requires it.
- Update the control module software if an outdated calibration is a known cause for that model, or repair the module input if proven faulty.
Can I keep driving?
The car can normally be driven, but book it in soon. A faulty reading can lead to incorrect charging, so keep an eye on battery condition and warning lights.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.