Yo Hayden,
WELCOME!
See these switch tests by Steve:
All '80-96 t/g wiring runs from the dash switch (F2TZ-14529-A
Motorcraft SW7071 out the firewall along the frame to the rear bumper up to the L taillight and into the t/g. '80-86 have a large round 3-wire connector in the LHR taillight well; those with rear defrost also have a 1-wire connector. All years with rear defrost have a ground ring screwed to the body in the taillight well. I think '87-91 have the large round connector in front of the taillight AND a smaller round 4-wire connector inside the frame at the LHR body mount. '92-96 only have the frame connector.
Normal operation is as follows:
RAISE from the dash switch:
Power flows thru fuse 14 thru the LB/BK wire thru the IP switch UP contacts thru the P/LG wire thru the key switch UP contacts thru the Y/R wire to the motor brushes, commutator, & windings; then it grounds thru the motor's internal CB, out thru the R/Y wire thru the latch switch thru the T/Bk wire thru the key switch DOWN contacts thru the Pk/LB wire thru the IP switch DOWN contacts to the Bk wire to the ground G201 in driver kick panel.
LOWER from the dash switch:
Power flows thru fuse 14 thru the LB/BK wire thru the IP switch DOWN contacts thru the Pk/LB wire thru the key switch DOWN contacts thru the T/Bk wire thru the latch switch thru the R/Y wire thru the motor's internal CB to the motor brushes, commutator, & windings; then it grounds out thru the Y/R wire thru the key switch UP contacts thru the P/LG wire thru the IP switch UP contacts to the Bk wire to ground G201 in driver kick panel.
Al
