The most likely problem for your problem is the child-lock switch in the console. If it has been accidentally left in the "off" position or if the switch or its wiring have failed, the rear windows will work from the console but not from the rear door switches. By my reading of the schematic, even a missing child-lock switch should still allow the rear windows to be operated from the console. If that is not the case, read on.

The '87 300D/TD and some other cars of the 124 era have stranded wiring in which the individual strands are too coarse. Over many years of bending back and forth in the rubber accordion that runs between the doors and the A and B pillars of the frame, the copper work-hardens and the strands begin to break. Eventually, there are so few that they cannot carry sufficient current and the windows stop working (this can also affect the puddle lamps in the bottom of the doors). In the case of my '87, the broken wires eventually protruded through the insulation and caused a short circuit so that I was continually blowing fuses.

Although a coincidence, it is entirely possible that the wiring to both doors has failed at about the same time. To test this theory as a possible cause, remove the door skin(s) and disconnect the wiring at the bottom of the door where there is a two-terminal screw connector. Those two wires go to the window motor. You can apply 12 Volts across those two wires and see if the motor will go up or down. Reverse the leads to make the motor go in the opposite direction. If that is successful then you know the motor is good. If it fails, the motor is almost certainly bad (assuming you have the right wires).

If the motors are good but still don't work from the console or door switches, then it is either a switch or a wiring problem. The switches I assume you know how to work on and there are many threads in this forum on repairing them. Wiring in the console is usually not a problem because there is no movement of the wires so they don't break.

To check the wiring in the B pillars, you need to remove the covering. The plastic cover at the bottom is held on by two Phillips-head screws and the pillar cover has a sheet-metal fastener at the top that clips into the B pillar itself. You will have to unreel some of the seat-belt to get the cover away from the B pillar so you can look inside. It may also be necessary to disconnect the wiring in the door so you can pull it partially through the rubber accordion -- if the wiring is broken it will probably be in the accordion, where all the bending takes place. Any broken wires that you find can be repaired or replaced and the door and B pillar put back together.

Note that my advice is for an unmodified car. If someone has been boogering with your car's wiring, all bets are off.

Jeremy

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
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