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Transfer Unit

The transfer unit pumps the urea-water solution from the passive reservoir to the active reservoir. There is a screen filter in the inlet port of the pump.

This pump is designed as a diaphragm pump. It operates in a similar way to a piston pump but the pump element is separated from the medium by a diaphragm. This means there are no problems regarding corrosion.

Fig 1: Identifying Transfer Unit
G06896088Courtesy of BMW OF NORTH AMERICA, INC.
INDEX EXPLANATION CHART

Index Explanation
1 Connection for transfer line to passive reservoir (inlet)
2 Electrical connection for pump motor
3 Connection for transfer line to active reservoir (outlet)