Coolant level sensors help monitor the presence of coolant in a car’s engine, and these devices also send a host of information to the vehicle’s computer. The location of the sensor varies from model to model, and some cars may have more than one.
The location of the coolant sensor varies according to the manufacturer and model of vehicle, according to the automotive website AA1Car.com. A typical configuration places the coolant sensor inside the intake manifold, but some manufacturers place the sensor inside the cylinder head. All sensors are situated so that one tip touches the engine coolant.
Coolant sensors use a temperature-sensitive resistor. This resistor remains highly resistant at cool temperatures, but resistance drops as the coolant temperature rises. If the sensor loses contact with liquid coolant, it sends a fault signal to the computer and triggers an indicator light.
In addition to detecting the presence of coolant, coolant sensors feed information to a car’s computer. Some vehicles may contain two coolant sensors -- one in each cylinder bank -- and some may feature one in the coolant reservoir.
