Help Needed to Clean Drain Tubes
 

I have an 05 Escalade and believe the drain tubes need to be cleaned. Does anyone have instructions on how to do this? I have water coming in through the passenger roof a/c-heat vent and the roof ac-heat control panel, but around the sunroof is dry. I dont understand..... Any ideas? Thank you.

Drains are typically "blown out" with compressed air. Drains are in the 4 corners of the pan/tray that hold sunroof. Front drains are easy to find, rears are some what of a "spray and pray" since there isn't easy access to them.