2670Mk Refrigerator Vent Exterior Leak

[RicknBobbie]

The attached photo shows a brown streak where there is a leak at the lower refrigerator vent. I recently re-caulked the exterior trim around the refrigerator vents at the rear of the camper, as well as cleaned and re-caulked the inside screws at the base. In October, we experienced a solid week of rain, but no external staining occured. When I checked it recently, the stain streak was back. I didn't see any indication that it was running down inside the wall from the vent above, and the roof seam is intact. The inside of the camper is dry. The caulking looks good. I am stumped.

The tail light needs the caulking replaced, so that part of the problem should be easy to solve.