There are a few "usual culprits".... first check to see that the plugs are still on at the passenger door both at its door switch and at the motor. They can come loose with opening and closing. That's not the mostly thing though. The most likely problem is a broken wire at the driver's side door post where the wire bundle pass from the body to the door.... from opening and closing, the wires eventually break in some form. The basic system operation has the "signal" (power / grd) pass thru the master control switch for the passenger side and then on to / thru the switch at the passenger door. So you may have a problem at the driver's side door post (ie. broken wire) or a similar condition at the passenger door... either one will result in similar symptom. I only 96 drawing but wiring colors are W/Y, T/LB, and also R/LB (4door) or LB/BK (2 door) just because of how the windows operate. Again this is for 96 and even that might be suspect as with most "non-official ford drawings" that seem to have differences here and there. Hope it helps a bit.
