RHS Seat -- No back motion

[DrJ]

I'm trying to figure out why and fix the cause of the passenger seat not moving back when using the electric switch (1987 300e/W124). All other functions work as they should.

I have pulled the switch, and it seems to work properly. That is, the resistance falls to zero for all of the switch positions between the appropriate narrow pin and one of the fat ones (presumably these are power). Yet when I try to jumper the connector in the door, nothing seems to happen for any of the "switches."

Do I understand properly how the switch works? If so, why did using a jumper not work? It would seem that either the connector or the wiring from the door to the body has failed. Is there a straight-forward way to figure out which, and which wire it might be?