Engine Oil Temperature Sensor, Basic Function - GF18.30-P-2000A

Engine All (4xWD, CAR) 

Example of engine oil temperature sensor 

Courtesy of MERCEDES-BENZ USA

Overview 

This document contains information on:

• General 
• Function 

General 

The engine oil temperature sensor detects the engine oil temperature.

Function 

The engine oil temperature sensor has an integrated precision resistor with a negative temperature coefficient (NTC).

The NTC resistor changes its electrical resistance according to the engine oil temperature.

The electrical NTC resistance decreases as the temperature increases (NTC thermistor).

The resistance variation results in a voltage signal. The combustion engine control unit calculates the engine oil temperature from the voltage signal.

The combustion engine control unit permanently evaluates the voltage signal. If the engine oil temperature is too high, a power output limitation is initiated by the combustion engine control unit.

Any fault in the engine oil temperature sensor is detected by the combustion engine control unit and entered in the fault memory.