51 16 ... Removing And Installing / Replacing Trim On Roller Sun Blind Of Left Or Right Rear Door

Unclip trim (1) and pull out in direction of arrow from door trim panel (2).

Fig 1: Pulling Out Door Trim Panel

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Installation: 

Engagement rails (1) of trim (2) must not be damaged.

Fig 2: Identifying Rails And Trim

Courtesy of BMW OF NORTH AMERICA, INC.