@jimkern the relay is located in the fuse box to the left of the steering column. Relay 4 is the One-Touch down relay and #5 is the Delay relay.
[image|3128889]
Only issue with that is, that there is one relay for all the windows.
[image|3128894]
That makes it unlikely that this is the issue for your F-150 since it is only the one window that does not work. I would check the single switch for the particular window as well as the individual motor. Use something like the Power WIndow section [document|32167] from the SM for the 1997-2004 Ford F-150 series to check it.