My sunroof has drains with hoses routed through the trunk into the rear quarters. There they connect to drains exiting under the car on either side of the gas tank. The antenna has a drain hose that connects to the drain also. If the hoses clog up they can eventually back up into the sunroof area. Take a wet/dry shopvac and try to vacuum them out from the bottom. Also, on one of my old galants, the sunroof hoses had become disconnected inside the rear quarters, where they had drained until my rear quarters were full of water. Pulled the trunk side liners out and could easily see where everything connected. Pulled the drain plugs and cleaned everything out. Reconnected and I was back in business...minus 20 pounds of water!