Component description for the coolant temperature sensor - GF07.04-P-6040BK

ENGINE 113.967 in MODEL 219

ENGINE 113.964 in MODEL 164.1

ENGINE 113.971 in MODEL 251

Location

The coolant temperature sensor is located at the front of the engine.

Task

The coolant temperature sensor detects the coolant temperature via an NTC resistor.

Fig 1: Identifying Coolant Temperature Sensor

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Function

The NTC resistor integrated in the coolant temperature sensor alters its electrical resistance in line with the coolant temperature. The NTC resistor is connected between ground and the ME control unit. When the coolant temperature sensor is unplugged, the voltage at the ME control is around 5 V.

NTC means "N egative T emperature C oefficient", which mean that the electrical resistance drops as the temperature increases (thermistor).

Example:

Coolant temperature	Resistor	Voltage
20°C	3100 ± 5%,	about 3.39 V
80°C	315 ± 5 %,	about 0.89 V

The connection assignment (polarity) of connection pin 1 and 2 is random.

Fig 2: Coolant Temperature Sensor Pin Connection Diagram

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.