61 13... Inline plugs, 3-, 6-pin, System Elo-Power 2.8
WARNING: This page is about a different car, the 2013 BMW 550i GT, 2012 BMW 550i GT, 2011 BMW 550i GT, and 2010 BMW 550i GT. However, it is still accessible from the selected car via links, so may be relevant.
Press locking hook (1) in direction of arrow and disengage. Then unlock locking hook (2) and remove lock.
Press down retaining hook with screwdriver (1) and pull out cable with contact towards rear.