Oil Pressure And Temperature Sensor
The oil pressure and temperature sensor is located next to the control valve/axial solenoid in the differential electronic module (DEM). The sensor is flushed with hydraulic fluid. The sensor gauges the temperature and pressure of the hydraulic fluid (measurement range 0-8 MPa). The sensor transmits signals about temperature and pressure to the control module. The control module uses the signal to adapt the system when the temperature, and therefore the viscosity, of the fluid changes.
If the temperature of the oil exceeds 105 °C then the clutch is depressurized and four-wheel drive is disconnected. When the temperature falls below 101 °C the clutch is pressurized again. The pressure of the oil is limited to max. 10.3 MPa by the safety valve.
Four-wheel drive does not function in the event of any fault in the temperature sensor, and the function is significantly reduced in the event of a fault in the pressure sensor.
The oil pressure and temperature sensor can be diagnosed.