it is very likely that your door panel window switch is bad. mine didn't last but six months and i have heard others having problems with these switches, as well. only thing to do is order a new switch from your Ford dealer as these are dealer item only. won't find them at local auto parts store. also, it's not that hard to remove your door panel and replace the switch (or switches). don't know really why the window switches go out my best guess is that the contacts go bad or stop making contact when used. good luck.
more than likely
Check to see if you are getting power to the motor - if so probably a bad motor Check the operation of the switch
Click on the link below Click on Owner Guides The Owner Guide ( which includes the fuse diagrams ) can be viewed online
Relay being activated
Your switch is bad or the window motor has gone out
how to put a power window back on track on a 1991 ford f150
behind rear seat
Check your fuses, check for power going into the window motor, exc.
Motor Oil Dipsticks is located on the drivers side engine compartment.
Image on the Firing order on a f150 2002?
The power distribution box ( which is " live " ) is located in the engine compartment , near the drivers side fender / brake fluid reservoir
Under dash in fuse panel; Relay Switch #2 (On left, second from top)