With Steptronic

Move selector lever (1) to "P" position (front stop of shifting gate).

Release screw (2). The cable (3) must remain easily movable axially in the holder (4).

Move ignition key to "0" position and remove.

Press interlock lever (5) downwards as far as it will go.

Tighten down screw (2). See Fig 1.

Fig 1: Adjusting Interlock (With Steptronic)

Courtesy of BMW OF NORTH AMERICA, INC.