Circuit voltage of engine coolant temperature sensor is high. What happened? The yellow light of the engine fault light is always on and cannot be eliminated.

The reason why the circuit voltage of engine coolant temperature sensor is too high is that the rear oxygen sensor is out of order, which can also be solved by adding resistance.

1. If the voltage is less than 4.9V, test the engine coolant temperature sensor signal circuit for high resistance or open circuit.

2. If the voltage is higher than 5.2 volts, test the signal circuit of the engine coolant temperature sensor for a short to voltage.

Supplementary method:

1, open the door

2. Pull down the hood switch.

3. Lift the hood.

4. Slowly unscrew the cover of the water tank kettle of the car and let off the high-pressure gas inside.

5. Add cooling water to the top of the car kettle.