GM Service Manual Online
For 1990-2009 cars only

A drain trough encircles the sliding window panel and leads to the drain hoses. The drain hoses are located at each corner of the sunroof module assembly. The two front drain hoses route down the windshield pillars and exit the front inner wheelhouse area. The two rear drain hoses route down the rear sail and the quarter panels and exit the inner rear wheelhouse area.

If you encounter a wet headliner or other water leak, inspect the following areas for the source of the leak:

    • The windshield
    • The rear window

Verify that the drainage system is not plugged or restricted. Use the following procedure:

  1. Using a one pint container, pour water into the drain trough with the sunroof window open.
  2. Inspect for water exiting the wheelhouse area of the vehicle.
  3. If the water flow is restricted, use a low volume of compressed air in order to clear the drain system. Do not blow the drain hose away from the housing drain spout.
  4. Retest the system.

If water drips from the headliner above the door, lower the headliner as required in order to inspect for a proper drain hose to drain spout connection. If necessary, use new tie wraps in order to secure the drain hoses onto the drain spouts.