Removing the trim from the left and right water channels

NOTE: Description is for left component only. Procedure on the right side is identical.

Removing the trim of the water channel

Release the clip (1).
Guide out the trim (2) in the area of the edge protection (3).

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Swivel the lower section of the trim (1) toward the center of the vehicle and guide it out with the guides (2) and (3).
Release the detent (4) and remove the trim (1) toward the center of the vehicle.

Courtesy of BMW OF NORTH AMERICA, INC.