Coolant temperature sensor
P0125
Insufficient Coolant Temperature for Closed Loop Fuel Control
The sensor that tells the computer how hot the engine is reads outside its expected range, or the engine isn't warming up as it should.
Fix it soon
Can I keep driving? For a short while, gently. Have it checked in the next few days, and stop if the car feels, sounds or smells different. The computer may fuel the engine as if it's cold, or the fans may not run when they should. Keep an eye on the temperature gauge.
Common causes
- A failed coolant temperature sensor
- Low coolant
- A thermostat stuck open
- Wiring or connector trouble
Listed roughly from most to least likely. The same code can have different causes on different cars.
What to do
- With the engine cold, check the coolant level. Never open a hot radiator cap.
- Watch the temperature gauge. If it climbs toward hot, stop.
- Have the sensor and thermostat tested.
General guidance. Your owner's manual wins. If a red warning light is on or the car drives differently, stop safely and get help.
Related codes
- P0115Engine Coolant Temperature Circuit
- P0116Engine Coolant Temperature Circuit Range/Performance
- P0117Engine Coolant Temperature Circuit Low
- P0118Engine Coolant Temperature Circuit High
Track this automatically in Tagwell Auto
Tagwell Auto keeps your car's service dates and mileage, so when a code shows up you know what was done last. With a Bluetooth reader for the car's diagnostic port (called OBD-II), the phone app can read the code itself.