Electrical feed pump
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The electrical feed pump is integrated in the coupling unit and is powered by the differential electronic module (DEM). When the engine is started and exceeds 400 RPM, the electrical feed pump receives power from the control unit.
The feed pump pumps oil to the annular pistons, whose rollers move into contact with the cam disc. At the same time the oil flows to the operating piston, so that the play in the multi-plate clutch unit is eliminated. The coupling is then able to react rapidly and regulate as required.
Four wheel drive is disengaged if there is a fault in the feed pump.
There are diagnostics for the feed pump.