I'll take a "guess" at the yellow wire,
If this is up front and by the area where the 7 wire cable that plugs into the truck comes in the camper.... That is the unused back up light wire in the 7 wire cable. Most times this is in a wood box with a fuse and or self resetting circuit breaker on the older campers.
Tell us a little more on the location of the mystery wire? Or did I guess right and win the prize??
The window. Somewhere... I thought I had a post on this. I cannot find it but here are the pics
In side the camper, on the newer campers, there is a series of screws all around the flange that hold a flange ring on. Take out all those screws and the will come out, heads up it might fall out or be stuck to the side of the camper by putty tape. May need a helper to hold it so it does not fall out. On the older campers, I think the screws are on the outside.
Once out and all cleaned up, wood fixed. Then use butyl seling tape around the flange of the new window and extra in any dips etc and put back in. trim off excess sealing tape that ozz'ed out. Warm days ozz more than cold days
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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