52 15 057 Removing and installing or replacing valve body for lumbar support/backrest width adjustment

Necessary preliminary tasks 

• Remove the REAR PANEL FROM THE FRONT SEAT .

Detach backrest cover (1) from backrest frame.

Fig 1: Disconnecting Backrest Cover From Backrest Frame

Courtesy of BMW OF NORTH AMERICA, INC.

Remove valve body in direction of arrow from backrest frame.

1. Valve body for backrest width adjustment
2. Valve body for lumbar support

Installation note: 

Check that the valve body is correctly seated in the backrest frame.

Fig 2: Removing Valve Body For Lumbar Support From Backrest Frame

Courtesy of BMW OF NORTH AMERICA, INC.

Unfasten plug connection (1) and disconnect.

Unlock quick connectors and detach air hoses (3) and (4 and 5) from valve body (2).

Valve unit for lumbar support: 

1. (3) Hose (black), lumbar support drive
2. (4) Hose (blue) in the upper lumbar support
3. (5) Hose (red) in the lower lumbar support

Valve unit for backrest width adjustment: 

Fig 3: Identifying Valve Unit For Lumbar Support

Courtesy of BMW OF NORTH AMERICA, INC.

1. (3) Hose (clear), lumbar support drive
2. (4) Hose (transparent), lumbar support, left
3. (5) Hose (transparent) lumbar support, right