52 24... Emergency actuator for rear seat backrest

WARNING: This page is about a different car, the 2008 BMW M3. However, it is still accessible from the selected car via links, so may be relevant.

Release hook of backrest lock
Backrest

Fig 1: Releasing Hook Of Backrest Lock

Courtesy of BMW OF NORTH AMERICA, INC.

Insert screwdriver for levering in snap-in hole of rear seat lock.

Press screwdriver to center of vehicle and in so doing press supporting point (1) of Bowden cable outwards.

Fig 2: Pressing Screwdriver To Centre Of Vehicle

Courtesy of BMW OF NORTH AMERICA, INC.