Can Someone Help Please With 91 Window Motor Problem

Discussion in 'Fox 5.0 Mustang Tech' started by steve san, Dec 1, 2013.

  1. Hi,
    I am new to this forum and would really appreciate some help please. I have just bought a nice one owner 91 Mustang 5.0 LX. It has a problem that is proving tedious as the passenger window will drive down but not up, drivers side window works fine but drivers side switch for passenger window will not drive up or down. I have read several things on this problem and to date I have done the following:
    Fitted new switches both sides and rotated the drivers window switch that is working to the non working window and still not working so I think I have pretty much eliminated a switch problem.
    Checked the pink wire both sides and have power and have 12v to the motor R/Y and Y/R wires when pressing up and down buttons.
    Checked the 2 ground wire on drivers side switch and have good ground.
    Checked continuity of wires all to no avail, so cant be a broken wire
    The motor I find is is new and was probably fitted to solve the problem when I connect direct to a battery it rotates clock and then anti clock when wires are reversed.
    I took the cover off the motor gear and it is not a ford gear it is aftermarket the 3 plastic bushes are very tight in the 3 lobes backside of the center gear in fact I am having trouble reassembling. Should they be that tight??
    Has anyone else had this problem with all the checking and fixes I have made? I am open to any suggestion and would really appreciate them.
    San Diego
  2. Disconnect the motor and use a test light in place of it. Connect the test light across the pins for the motor wiring connector. Turn the ignition switch to Run and test to see if it lights up in both the up & down positions. Do the test with both the driver's side and passenger side. This will eliminate the switches and wiring as being the problem.

    Diagram courtesy of Tmoss & Stang&2birds


    See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring Everyone should bookmark this site.

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  4. jrichker Thank you for that it was most helpful and to date I have proved it is not the motor as the window down wire R/Y lights the lamp and the window up wire Y/R does not light the lamp. I have found that on the drivers side the pink has no power when ignition is on so it does not power the Y/B wire that goes to the passenger side. I ran out of daylight so will find a live feed to connect to the drivers switch tomorrow. Looks promising. Thanks again
    San Diego
  5. I finally fixed the problem which was two broken wires somewhere in the loom or a connector out of sight and reach. I cut the two wires that join both switches y/b and r/y on the passenger side and ran two wires through the car to test and it worked fine so I created a new two wire loom and threaded it side to side under dash and through door rubber boots into door cavities to switches, it was not easy but problem solved.
    Steve San Diego
  6. Cool, I'm glad you got it fixed.