last week my drivers side window switch stopped working so on xmas day after lunch I pulled the centre console apart.
1. unplugged the window switch unit
2. unclip the plastic tabs that hold the unit together(be gental)
3. blow out all rubish,hairs & dust
4. unclip the switch which is affected (1 side of switch plastic knob will be bigger)
5. take rubber cover off
6. tip upside down over a table & pick up terminals & any thing else that falls out
7. inspect the terminals that fell out aswell as the contacts inside if they are dirty like mine was get a flat head screw driver and scrape the contact clean
8. clean terminals before placing back on to the contacts & make sure terminals are sitting the right way or switch will jam
9.put the rubber cover back on aswell as the switch
10. reconect the plug & test before reinstalling the unit back in the console if all goes well put every thing back into place and ya rolling

that has happened to me several times. My dad burnt out the driver's switch on his NCII and we had to drive to the nearest dealership, which was 20 minutes away, and on a raining day, with his driver's window down, only about 1/3 of the way, and replace the whole switch pad. I may need to check the switch pad on my NL real soon, as i wound down the driver's window, went up to the shops, and then when i went to wind the window back up, it wouldn't move - dirty switch contact.

yeah most elec switches will eventually get dirty and stop working, specially with only 12v.

Sorry to change the subject, but is the Fordmods "Shop" still around? I want to get a couple of those modules that automatically shut electric windows on locking the doors with the keyfob.

with the switch contacts its not really dirt. its carbon build up from sparking just before or after contact is made, its alot more common on 12V becuase of the high drag of current. the best way is to use CRC co contact cleaner and also use grease or vasaline over the contacts and sliders to stop corosion from moisture (spilt drinks!)