OBD-II FAULT CODE
B2456
Aux Heater Coolant Sensor Circuit Short to Ground
Meaning, symptoms, likely causes, diagnostic checks and repair guidance for B2456.
- Body/accessory warning lamp or feature not working
- Temperature gauge abnormal
- Overheating or slow warm-up possible
- Low coolant
- Faulty thermostat
- Coolant temperature sensor/wiring fault
- Cooling fan issue
- Wire shorted to chassis/ground
- Check related fuses, connectors, grounds and switch/module power supply
- Check coolant level only when engine is cool
- Compare scan-tool temperature to actual temperature
- Inspect harness for rubbing/pinch points and check resistance to ground
- Repair leaks, replace thermostat/sensor/fan component after confirming fault
- Repair insulation/harness damage or replace internally shorted component
Related Codes
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Disclaimer: Information is provided for general guidance only and may not apply to all vehicles. Always consult a qualified technician.