52 14 ... Replacing left flex shaft for longitudinal seat adjustment drive
WARNING: This page is about a different car, the 2005 BMW 545i and 2004 BMW 545i. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect electrical plug connection.
Lift drive (1) and flex shaft (3) out of guide (2) in direction of arrow.
Detach flex shaft (3) (plug connection).
Loosen screws (1).
Remove drive (4).
Detach flex shaft (3) with holder (2).