So I have another roof leak on my 2003 Disco. This one is a head scratcher, because I pulled the headliner expecting my other drain tube to be leaking (I repaired the passenger drain last year). Nope, it’s dry and intact. At this point everything is dry since the leak was found, so I ran at least 30 gallons of water over the entire roof to try and replicate the leak. No leaking from the drain tubes and I can visualize all 4 of them draining. The bolts from the stock roof racks are dry, and there are no water trails anywhere to be found.literally can’t replicate the leak. It only seems to pop up in the front middle of the cab, dripping from the sunroof switch and cabin light area and only after it’s been sitting all night in the rain. I’ve attached some photos.. any ideas on this?

 

Mine does something similar, but only when I power wash it - leaks all over the mirror and radio. I've stopped power washing it and haven't cared enough to track it down.

 

Could this be windshield seal? It seems unlikely that it would run up to the dome light from the windshield but water does weird stuff.

 

Windscreen seal would be my guess as well.

 

That's still most likely sunroof issues. Pull the headliner and driving it like that a week or two to find all the leaks

 

Have you poured water through the drain tubes to verify they are free flowing? A partial clog could prevent the water from escaping fast enough, to the point it overflows the cassette.

 

and remove to complete plastic cover that holds the interieur light and sunroof buttons etc. so you can get a good view while pouring water over the sunroof.

 

I'd bet it's coming from between the plastic frame and the metal roof of the car -- leaking there, that "bond" breaks over time. This leak is completely unrelated to your drains not being clogged or drain tubes working properly or sunroof to glass seals. Water leaks between the roof of the car under that plastic frame on top of the car, in other words.