Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection

ENGINE COOLANT TEMPERATURE SENSOR
The Tech 1 scan tool displays engine coolant temperature in degrees Celsius and Fahrenheit. After engine is started, the temperature should rise steadily to about 90°C (194°F) then stabilize when the thermostat opens. If the engine has not been run for several hours (overnight), the Engine Coolant Temperature (ECT) and Intake Air Temperature (IAT) should be close to each other.