class c upper clearance lights

They are in the parking light circuit have you checked to see if your chassis parking lights work? If not, I would check the parking light fuse for beginners.

Has the water resistance been inspected and repaired if necessary?

All other lights work

They go in sections of pos wire around the top of the Rv. If one light in that section loses its pos wire connection the whole section goes but the other sections work. Pull each light in that section that does not work to find the "open".

none of the five front upper lights have power, I used a booster pack to feed that section of lights. the wire that feeds them has no power & I don't know where it comes from

Ok, say the wire for pos is green like on some. Dowm below there will be a branching of green wires going up to the sections. It seems that branch's wire has come loose down there.

I fixed a problem like that I could not find the right way, by running a wire from the pos of the next section's nearest light to the pos of the dead section's nearest light. So now just one big section. Covered the joining wire up there with white Gorilla tape so it looks fabulous :)

unfortunately I can't find where that wire comes from

I added the fix I did to previous post.

Also there are no other lights close to these ones

Run a new hot wire and forget the old one.