Fuel Pressure Sensor, Component Description - GF47.20-S-2030S
ENGINE 642 in MODEL 906
ENGINE 651 in MODEL 906
Shown on engine 651.940
Task
The fuel pressure sensor detects the fuel pressure (actual pressure) of the fuel pump with fill level sensor (M3/5) (for model 906).
The fuel pressure is evaluated by the FSCU (N118/5) (for model 906) for the load-dependent actuation of the fuel pump with a fill level sensor (for model 906).
Information about the current fuel pressure is also transmitted as follows:
- from the FSCU (for model 906) via the engine-CAN (CAN C) to the CDI control unit (N3/28) (with engine 651) or CDI control unit (N3/30) (with engine 642)
- from the FSCU (for model 906) via the drive train sensor CAN (CAN I) to the CDI control unit (N3/28) (with engine 651)
Function
A capacitive measuring element integrated in the fuel pressure sensor detects the fuel pressure.
When fuel pressure increases, the gap between the capacitor electrodes decreases. The capacitance, and therefore the signal voltage, thus increases in proportion to the fuel pressure.
The signal voltage serves the FSCU (for model 906) as information about the fuel pressure.
The fuel pressure sensor measuring range lies between 0.5 and 10 bar.