OBD-II FAULT CODE
B2457
Aux Heater Coolant Sensor Circuit Open
Meaning, symptoms, likely causes, diagnostic checks and repair guidance for B2457.
- 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
- Open circuit
- 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
- Check connector fitment and continuity from module to component
- Repair leaks, replace thermostat/sensor/fan component after confirming fault
- Repair open wire/connector or replace the failed component after continuity test
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.