Sensor, Coolant Temperature, Engine

Coolant Temperature Sensor, S54 Engine

Coolant temperature sensor, S54 engine
The temperature sensor is screwed into the cylinder head. A varistor (NTC = Negative Temperature Coefficient) serves as the measure for the coolant temperature. A resistor of this kind is also used to sense the radiator outlet temperature.

The coolant temperature sensor, S54 engine, also serves as a measured variable for the following functions:
- Start volume calculation
- Injection volume calculation
- Nominal idle speed

In the event of the sensor failing, a fault code is entered in the DME control module and a substitute value is calculated from the value of the intake air temperature sensor with the aid of a temperature model.