51 22 004 Adjusting rear left or right door detent (lock wedges)
WARNING: This page is about a different car, the 2006 BMW X5, 2005 BMW X5, and 2004 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.
Operation is described in:
Adjusting left or right front door. Refer to 41 51 004 Adjusting left or right front door .