ENGINE | 642 in MODEL 461.392 |
M3 | Fuel pump (FP) |
P47.20-2339-11
With code K86 (Additional tank 53l) |
M3/1 | Fuel pump for the auxiliary fuel tank |
6 | Splash bowl |
P47.50-2112-11
Location
The fuel pump is located on the outside of the fuel tank. For vehicles with code K86(Additional tank 53l) there is also a auxiliary fuel tank fuel pump in the swirl pot within the auxiliary fuel tank.
Task
The fuel pump provides a sufficient quantity of fuel to the high-pressure pump and at the required pressure. The auxiliary fuel tank fuel pump (with code K86(Additional tank 53l)) pumps fuel as required out of the auxiliary fuel tank into the fuel tank (manual range extension).
Body
The fuel pump and the auxiliary fuel tank fuel pump (with code K86(Additional tank 53l)) are 2-stage dynamic pumps.
Function
The functions of the fuel pump and the auxiliary fuel tank fuel pump (with code K86(Additional tank 53l)) differ as follows:
The fuel pump is actuated over the fuel pump relay (K27) by the CDI control unit (N3/9). It draws the fuel from the fuel tank through the fuel filter. The fuel pump then pumps the suctioned fuel through the fuel filter to the high-pressure pump.
For vehicles with code K86(Additional tank 53l) the additional tank control unit (N118/6) us actuated over the auxiliary pump switch (S36/2). The additional tank control unit responds by switching the auxiliary fuel tank fuel pump on over the additional tank relay (K27/8). The auxiliary fuel tank fuel pump then suctions in the fuel out of the auxiliary fuel tank and pumps the suctioned fuel into the fuel tank.