Engine oil pressure/temperature sensor
The engine oil pressure/temperature sensor measures the absolute pressure of the engine oil and its temperature. The measured values are output as a pulse-width-modulated signal.
The measuring procedure is based on a micromechanical piezoresistive pressure sensor (silicon) which supplies an output signal proportional to the pressure. Temperature measurement is performed by way of a diode.
The sensor measuring range is 0.5 bar to 10.5 bar at permissible temperatures between -40 °C and 160 °C. The sensor is operated with a voltage of 5 V.
|1||Engine oil pressure/temperature sensor||2||three‐pin plug connection|
Structure and inner electrical connection
The engine oil pressure/temperature sensor is connected by a 3-pin plug connection.
The engine oil pressure/temperature sensor receives its earth/ground and a supply voltage of 5 V from the engine control unit.
The pulse-width-modulated signal is split into 3 fixed cycles. The first cycle is for synchronisation and diagnostic purposes. The second and third cycles transmit the temperature and the pressure respectively.
|1||Oil pressure sensor||2||Oil temperature sensor|
|5 V||5 Volts, supply voltage|
|PWM||Pulse-width-modulated signal, engine oil pressure/temperature sensor|
|Terminal 31E||Terminal 31, electronics earth (ground) both sensors|
Nominal valuesObserve the following setpoint values for the engine oil pressure/temperature sensor:
|Supply voltage||5 V|
|Pressure measuring range||0.5 to 10 bar|
|Maximum power consumption||15 mA|
|Temperature range||-40 °C to 160 °C|
General notesThe sensor has self-diagnostic capability, enabling the temperature signal and the pressure sensor signal to be diagnosed separately. The diagnosis result is contained in the pulse-width-modulated signal and evaluated by the engine management system.
Failure of the component
If the engine oil pressure/temperature sensor fails, the following behaviour is to be expected:
- Fault entry in the engine control unit
- Emergency operation with substitute value