A few years ago I checked with Ford and the bulb was available for about $13.00, as I recall. I purchased a bulb at an electronics store for 60¢. The leads were a bit short, so I cut the leads off the factory bulb and soldered them on the new bulb leads to extend them. Bulb still working. My notes at the time:
05-OCT-03, 75,800 mi. - Bulb from Ford Electronics (60¢). Part number 8640, 12V. Transferred green bulb cover and spliced additional lead to lengthen.
I have about 158,000 miles now.
An LED is a good choice.
Found this (I don't remember the author, but it was from this site):
I may get around to posting some pictures but here is the source for the bulbs. Parts Express has the bulbs and the colored lamp covers. Not only can you replace the bulbs but you can do a color change if you’re in to that sort of thing. The headlight switch and the rear window switch are 5mm bulbs 12v. The fog light switch is a 3mm bulb 12v. The covers come in several colors for 3 and 5mm bulbs.
Here's the goods:
• bulb 3mm 070-235 .45
• bulb 5mm 070-265 .45
• cover green 10pk 070-082 3mm $1.70
• cover green 10pk 070-092 5mm $1.70
If you try to repair these you should look for a small twist off socket on the switch. They have to be removed from the plastic dash holder and sometimes taken apart further to find the bulb. As I mentioned before, mine is a 2001, yours may be different. I did not list all of the other color part numbers so please do your homework if you’re going to order parts. Once you find one of the items on that website it should be easy to find all the others. Also, the part numbers may change so make sure you are getting what you need.
I ordered extra but if I had to give a cost for repairing the three switches I would guess $9.44. Included in that was $6.39 for shipping.
And a link to a discussion on this site:
