Fuel Pump Control Unit: Description and Operation

GF47.40-P-2001AMG Component Description For The Fuel Pump Control Unit







Fuel pump control units are located in the middle under the rear bench seat.







Fuel pump control units are located on the bottom left in the front passenger footwell.







Fuel pump control units are located on the bottom right in the luggage compartment.







Fuel pump control units are located on the front right in the luggage compartment.







Fuel pump control unit is located in the left footwell in front of the 2nd seat row.







The fuel pump control unit is located on the left under the rear bench seat.







Fuel pump control units are located in the left footwell in front of the 2nd seat row.

Task (except model 216, 221)
The left fuel pump (M3/2) is actuated via the left fuel pump control unit and the right fuel pump (M3) is actuated via the right fuel pump control unit, single phase.

Function (except model 216, 221)
Fuel supply is controlled and monitored by the ME-SFI [ME] control unit (N3/10) and the left and right fuel pump control units

Switching on of the fuel pump takes place via the discrete signal "EKP run" (Electrical Fuel Pump) from the ME-SFI [ME] control unit to the Fuel pump control unit. In order to control fuel pumps the ME-SFI [ME] control unit detects the current fuel pressure via the fuel pressure sensor (B4/15) and transmits the PWM signal (pulse width modulated signal) "fuel requirements" representing the current fuel requirements to the fuel pump control unit. This analyzes the PWM signal and actuates the fuel pumps appropriately, single phase. The fuel pressure is regulated to be variable from between 4.0 and 5.5 bar depending on the fuel pressure. The fuel pump are actuated independently of each other.

Task (for model 216, 221)
The left fuel pump (M3/2) is actuated by the left fuel pump control unit, 3-phase.

Function (for model 216, 221)
The fuel supply is controlled and monitored by the ME-SFI [ME] control unit (N3/10) and the left fuel pump control unit

Switching on of the fuel pump takes place via the discrete signal "EKP run" (Electrical Fuel Pump) from the ME-SFI [ME] control unit to the fuel pump control unit.

In order to control the fuel pump the ME-SFI [ME] control unit detects the current fuel pressure via the fuel pressure sensor (B4/15) and transmits the PWM signal (pulse width modulated signal) "fuel requirements" representing the current fuel requirements to the fuel pump control unit. This analyzes the PWM signal and actuates the fuel pump appropriately, single phase.

The fuel pressure is regulated to be variable from between 4.6 and 5.5 bar depending on the fuel pressure.

Input signals:
- Terminal 15
- Circuit 30
- Circuit 31
- Discrete signal "electric fuel pump run" (from ME-SFI [ME] control unit)
- PWM signal "fuel requirements" (from ME-SFI [ME] control unit)

Output signals:
- Fuel pump + (for model 216, 221 3-phase (3x+))
- Fuel pump -

Diagnosis (except model 216, 221)
Both fuel pump control units are connected to the CAN data bus diagnosis (CAN-D).

Diagnosis (for model 216, 221)
The fuel pump control unit is connected via the drive train CAN data bus (CAN-C) with the ME-SFI [ME] control unit by which diagnosis of the fuel pump control unit takes place.

Discrete signal: signal with a certain voltage value.