The sunroof drains are an aspect of your car that you probably rarely, if ever, think about. Though the sunroof is sealed to keep most moisture out, some moisture and water does come in through the gap between the sunroof and the car itself. The moisture is then drained out of the vehicle through the sunroof drains, which run from inside the roof area and exit somewhere else. If the drains become clogged, it can make your interior smell musty and eventually create a major problem. Your car’s sunroof drains should be cleaned regularly.
Locate the drain holes. Depending on your vehicle, the location of these may vary, though the front drain holes in most cars exit in the doorjamb or under the car. The rears may drain under the rear bumper or the top of the rear hatch jamb area. Consult a workshop manual for your specific model.
Clean off any dirt, leaves and debris around the drain holes. Twist and squeeze the rubber ends of the drains where they exit the car. This should let out some of the trapped water and debris that is stuck in the drain.
Open the sunroof all the way so that you can see the drain holes. Test the flow of each drain by pouring a small amount of water (about ¼ cup) down the openings of the drain where they are located near the sunroof. These should be self-evident and located in the front and rear corners of the sunroof area. Check to see if the water is flowing out of the exits for the drain holes.
Blow compressed air into the drains if there is no water coming out of the rubber drain exits. If the water still does not drain out, use a piece of flexible wire to snake it down the drain hole to dislodge the debris. Twist and squeeze the rubber ends of the drain to help release the dirt and debris. Pour another small amount of water down the drain once it is unclogged to rinse it out.