i had this issue in my 91 on both sides. mine was due to broken wires in the rubber conduit between the lower a-pillar and the door itself. pull the corresponding door panel off and then unhook the connector inside the door itself. then when theyre seperated you can release the tangs holding the main harness to the door and pull it out through the doorjam area. pul back the rubber and inspect for broken wires. i had this problem and mine were broken off flush with the connector. I had to pull the treminal out of the connector and resolder a new wire to it and then reconnect it to the main harness. i had to go up about 3 inches til i found a decent point on the harness wire to make a quality connection. There must have been water intrusion in there causing corrosion and then it broke after opening and closing the door all the time. after wards i tested it and wala it fixed it. If you look at the wiring diagrams it shows theres a 3 wire connection that runs to the door latch. one wire is a constant signal return to the seatbelt module. the other 2 are for circuit connections telling the module when the door is either 1 open, or 2 closed. simple circuit but it tells you why it make the seatbelt go forward but not back. Ive helped a buddy do it to his teggy when it was stuck back and never went forward. he bought a latch and it didnt work. Best of luck to ya. hope it fixes it. If there isnt any wires broken try to jumper the 3 wire connection in the door panel itself that goes to the latch. its 3 pin so all you do is jumper the middle pin to one of the outside pins. the middle one is the constant signal return to the module that i just talked about. good luck
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