61 13 ... In-Line Plugs, 2-Pin, System JPT ELA
WARNING: This page is about a different car, the 2007 BMW 550i and 2006 BMW 550i. However, it is still accessible from the selected car via links, so may be relevant.
Press lock (1) in direction of arrow and slide plug forward.
Press lock (1) downward and slide out to one side.
Unlock contact with special tool 61 1 136 and pull out cable (1) and contact towards rear.