Here is a good thread to check out:
http://www.explorerforum.com/forums/showthread.php?t=243401
Here is a great link for troubleshooting the power windows, it's for the '02 but should help out, thanks to
theofam for this great link
Dead Link Removed
Pinpoint Test E, starting on page 22 is for troubleshooting the rear passenger window. Page 25 outlines testing the rear passenger switch.
I downloaded it for future reference. I don't think it's available for download anymore. If you want I can email it to you, just shoot me a PM with your email address and I'll fire it off.
I have the workshop manuals and wiring diagrams for the '02. I can scan and send if needed.
Good luck with the fix. Electrical gremlins can be a huge PITA!