An engine coolant sensor is a device that measures the temperature of the coolant in an internal combustion engine. It is typically located in the cylinder head or radiator hose and provides input to the engine’s electronic control unit (ECU) to adjust the fuel mixture and ignition timing. A faulty engine coolant sensor can lead to a number of problems, including engine overheating, poor fuel economy, and decreased performance.
Testing an engine coolant sensor is a relatively simple procedure that can be performed at home with a few basic tools. First, disconnect the electrical connector from the sensor. Next, use a multimeter to measure the resistance between the sensor’s terminals. The resistance should be within the manufacturer’s specifications. If the resistance is too high or too low, the sensor is faulty and should be replaced.