I have a 90 Bronco and had the dealer replace the switch located on the dash that controls the rear window. The window now goes up when the switch is in the down position and goes down when the switch is in up postion. I had another dealer put in another switch with the same results. I have checked and the switch part number is what is specified by Ford.
If you can try turning the plug on the back of the switch over. If that's not possible, inspect the wiring going to the tailgate from the main body. Remove the rubber boot and inspect each wire carefully. Sounds like it was repaired once and two wires got hooked up backwards. HTH. -Jim
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