Same symptoms for me. I had broken wires in the door hinge. They are hidden inside woven insulation in the accoridan rubber thing between the car and door. I added new wire from the pillar to the door.

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1968 220D, w115, /8, OM615, Automatic transmission.
My 1987 300TD wagon was sold and my 2003 W210 E320 wagon was totaled (sheds tear).