Coolant Temperature Sensor
WARNING: This page is about a different car, the 1993 Mercedes-Benz 300E. However, it is still accessible from the selected car via links, so may be relevant.
Coolant temperature sensor is a Negative Temperature Coefficient (NTC) type sensor. As sensor temperature increases, resistance decreases. Coolant temperature sensor converts engine coolant temperature to a voltage signal. The LH control unit uses engine coolant temperature to control fuel injection duration. See Figure .