61 13... Circular connector, 13-pin, system D2.5
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Pull off rubber grommet (1).
Carefully pull out lock (2) in direction of arrow.
Move lower section of connector (3) in direction of arrow until retaining lugs (4) snap into release groove (5).
With special tool 61 0 303 , press down retaining lugs (6) of corresponding contact and pull out cable.