I think you have a T2499, is that correct? We had one of them. Great camper.
If you can see the water on the inside of the camper, this is a concern there is more damage above the ceiling.
Can you post pictures of the caulk on the roof in the area of the leak inside? We can tell sometimes how the caulk looks if that is the entry point.
And while you are on the step ladder, feel the roof in this area. The roof is rubber bonded to a thick corrugate board (not fluted cardboard but thick dense corrugate)
By gently pressing down on the rubber in the area of the leak, feel for a very super spongy effect, like a tire tube. Then go over on an area many feet (10 plus feet) and feel where you believe there is no leaks. There is a natural flexing texture to the roof structure, (it is "not a walk on directly roof") but good roof does not have the tire tube sponge feel. When that happens the corrugate board has become wet and separated from the rubber and the roof has to be lifted up in that area and all wet and rot removed and repaired.
This ongoing post may be of help. It shows many pics of the roof structure. At this point, you do not know if it is this bad yet, however this camper had zero signs inside of a leak, but we found it from the top down and then uncovered a real situation. If you have a leak, you need to find the source, and correct the damage before you seal it back up.
Hope this helps. Pics of the new roof will be forth coming on that post. In your case, a repair may be able to be made in just the corner area if the damage is that small. This has been done many times before. We had 3 bad corners.
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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