61 13... Round connector, 13-pin, system D2.5
Pull off rubber grommet (1).
Carefully pull out lock (2) in direction of arrow.
Move connector lower section (3) in direction of arrow until the retaining lugs (4) snap into release groove (5).
With special tool 61 1 132 (press-out tool) press back arrester hook (6) of appropriate contact and pull out the cable.