Tracking a pesky leak

I've been resealing my old R V roof and used a product called Sikaflex on the side seams that done a real nice job or, at least looks like it did. I bought Dicor self leveling sealer for the flat seams like my sky lights witch I started today. I liked how the Dicor flowed out and leveled and I was confident I had done a good job. now I wonder if I'll have the same experience. I like the pressure test idea for leak location but could you actually cause a leak by blowing a seal. the only other thing I could think of is coloring water and pouring it in suspect areas but,then you have a problem of staining the ceiling.so maybe look the roof over and ID areas then pour clean water over one at a time till you find the one that hits.