Checking Fluid Level In Hydraulic Unit:

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Necessary preliminary tasks:

Remove right luggage compartment wheel arch trim, refer to 51 47 161 REMOVING AND INSTALLING / REPLACING RIGHT LUGGAGE COMPARTMENT WHEEL ARCH TRIM

Test requirements:

Open rear lid (motor-driven) once and close again, this bleeds the system.

Open rear lid again (motor-driven).

Unscrew nuts (1).

Fig 1: Removing Hydraulic Unit

G03291422

Courtesy of BMW OF NORTH AMERICA, INC.

Remove holder and pull out hydraulic unit (2).

Disconnect plug connections (3).

4 Hoses
5 Cable holder

Hold hydraulic unit with drive (1) all round vertically upwards.

Fig 2: Holding Hydraulic Unit

G03291423

Courtesy of BMW OF NORTH AMERICA, INC.

When rear lid is fully opened (cylinder retracted), fluid level (2) must be in area (A) of marking (3).

Correct measurement:

Fig 3: Checking Fluid Level

G03291424

Courtesy of BMW OF NORTH AMERICA, INC.

Set hydraulic unit (1) down on a horizontal surface (4).

Damper (3) and valve (5) must not rest on surface.

Check distance (B) from middle of marking (2) to lower edge of hydraulic unit (1).

B = 45+/-1 mm

Fluid level must be in area (A) of marking (2).