GF47.50-P-2020MOR Component Description For Fuel Pressure Sensor

GF47.50-P-2020MOR Component Description For Fuel Pressure Sensor
- ENGINE 275.9 in MODEL 230.4 as of model year 2009 / AEJ 08 model refinement package





View of the underfloor (shield removed) (for engine 275.954/81)
B4/7 Fuel pressure sensor
Arrow: Connector

Location
The pressure sensor is located in the LH underfloor in front of the rear axle.





View of fuel tank at the front (for engine 275.983 with code (P99) Special model "AMG Black Series")
B4/3 Fuel tank pressure sensor
B4/7 Fuel pressure sensor

Location
The fuel pressure sensor is located above in the fuel filter housing.

Task
The pressure sensor detects the fuel pressure (absolute pressure) in the fuel line to the fuel distribution rail.
The fuel pressure is evaluated for requirement-oriented actuation of the fuel pump (M3).

Function
The fuel pressure is measured by a capacitive measuring element integrated in the pressure sensor.

When fuel pressure increases, the gap between the capacitor electrodes decreases. The capacitance, and therefore the signal voltage, thus increase in proportion to the fuel pressure.

The signal voltage serves the fuel system control unit (N118) for engine 275.954/81 or the ME-SFI [ME] control unit (N3/10) for engine 275.983 code (P99) Special model "AMG Black Series" as information about the fuel pressure.