Oil sensor component description - GF18.40-P-2000SM

ENGINE 113.986

ENGINE 113.987

ENGINE 113.988

ENGINE 113.989

Model 203, 209, 171

Fig 1: Locating Oil Sensor (Oil Level, Temperature And Quality) - Model 203, 209, 171

Courtesy of MERCEDES-BENZ USA

The oil sensor is located at the rear at the oil pan.

Task

The tasks of the oil sensor are:

Detecting oil level
To measure the oil temperature
Detecting oil quality for demand-based oil change interval display.

Model 215, 220

Fig 2: Locating Oil Sensor (Oil Level, Temperature And Quality) - Model 215, 220

Courtesy of MERCEDES-BENZ USA

The oil sensor is located in front of the front axle, at the bottom right at the oil pan.

Body model 171, 203, 209

Fig 3: Identifying Oil Sensor (Oil Level, Temperature And Quality) - Body Model 171, 203, 209

Courtesy of MERCEDES-BENZ USA

Body model 215, 220

Fig 4: Identifying Oil Sensor (Oil Level, Temperature And Quality) - Body Model 215, 220

Courtesy of MERCEDES-BENZ USA

Function

The oil sensor operates in accordance with the capacitive measuring principle and features integrated electronics which convert the three signals into a PWM signal.

The PWM signal is sent to the ME control unit (N3/10) and then continues on via the CAN databus to the instrument cluster.A1

Oil level and oil quality are detected on the basis of the capacitance of the engine oil (dielectric). The capacitance of the engine oil is as much as 6 times greater if the oil quality is poor.

The measuring range for the oil level is 80 mm (normal level ± 40: approx. c3 mm), measuring accuracy approx. ± 3 mm.

The oil temperature is detected by an integrated temperature sensor (NTC resistor).

The voltage for the oil sensor (approx. 5 V, sensor voltage) is supplied by the ME control unit.

Faults at the oil sensor are detected by the ME control unit and entered in the fault memory.