There are four small holes on the four corners of the moon roof. The best way to clean these holes out is to blow them out with some type of air blower - an air tank or a can of compressed air.
If it's leaking the moonroof drains near the front are plugged.
It is up in the front corners of the moonroof it might be a hidden by the moonroof track. If you take a look you should see a pen size hole and it drains into your wheel wel.
Clean the drains.
Ideally through the fixture trap or clean out and NO chemicals
How do you clean out bottom drains of quarter panel on a 2001 325i?Read more: http://wiki.answers.com/How_do_you_clean_out_bottom_dains_of_quarter_panel_on_a_2001_325i#ixzz1YzPcBxqW
Clean drains,toilet bowls,etc.
Yes, fleas can live in drains. To prevent them from infesting your home, you can regularly clean and disinfect your drains, use flea control products, and treat your pets for fleas.
To prevent clogs in drains, use bell traps to catch debris and regularly clean them out. Additionally, avoid pouring grease, hair, or large objects down drains to maintain proper flow.
To clean the sunroof drains on a 2003 Ford Expedition, first, locate the drain tubes, which are typically found at the four corners of the sunroof opening. Use a flexible wire or a plumber's snake to gently clear any blockages in the tubes. You can also flush the drains with water using a funnel to ensure proper flow. Ensure the drains are clear by checking that water drains out from the bottom of the vehicle, usually near the wheel wells.
The best equipment used to clean drains are snakes, augers, plungers, and chemicals similar to Draino to disolve clogs. Be very careful or you may end up having to call a professional. This should sum it up nicely. http://www.howtocleanthings.com/how-to-clean-a-drain.htm
sunroof pops up,moonroof slides back.
remove the headliner remove the old moonroof install new moonroof replace headliner