The TCU box caused my illumination not to work, also with the brake lights. Try this:
http://www.nicoclub.com/archives/fix-fo ... ights.html
Just replace the TCU box with a junkyard one, that the best way IMO. But if you have a friend, you can test it with his first to make sure that is it. Make sure you're not blowing fuses for parking lights also, that's another problem i ran into down the line.