The computer sees a fault in the coolant temperature sensor circuit. The driver may notice a hard start, high consumption or the fan running all the time.
Likely causes, most common first
- Faulty coolant temperature sensor
- Damaged wiring
- Corroded connector
- Low coolant level around the sensor
Parts usually involved
- Coolant temperature sensor
- Sensor connector
Test before you replace
Compare live coolant temperature with an actual measurement and test the wiring.
General guidance for generic OBD2 codes. Always follow the maker's procedure for the car in front of you.