The function of water temperature sensor is relatively simple, that is, through the change of its internal resistance, the current passing through the sensor changes to drive the change of water temperature meter, and indirectly tell people the working temperature of the engine.
If there is a problem, an error signal will be provided to the engine control unit. For example, when the car is hot, it provides an engine low temperature signal. Does your car need to be sprayed with more oil, so it looks a little waste oil?