type of coolant sensor

[alwaleed]

What are the types of coolant sensors in a car?

[lonely]

It’s of two types actually:

NTC and PTC: negative/positive temperature coefficient. 

[alwaleed]

And how do these work?

[lonely]

The coolant sensors change the resistance as per the temperature. The negative temperature coefficient decreases the resistance when the temperature in the car is hot/rises. The positive one, on the other hand increases the resistance when the temperature is high.