GM Service Manual Online
For 1990-2009 cars only

Drain Hose Routing

A drain trough encircles the sunroof window panel and water is drained off by the hoses located at each corner of the housing. A drain channel spans across the sunroof module at the rear of the window panel and directs water into the trough.

  1. Ensure that the front drain hoses are routed down the windshield pillars and out the center of the front pillar between the door hinges. Ensure that the hoses are not kinked. Replace any torn or cracked hose. Refer to Sunroof Housing Front Drain Hose Replacement .
  2. Ensure that the rear drain hoses are routed through the rear pillars and out of the rear lower quarter panel. Ensure that the rear hoses are properly routed in the metal roof slot and are attached in place. Replace any torn or cracked hose. Refer to Sunroof Housing Rear Drain Hose Replacement .

Plugged Drain Hose

If a waterleak has occurred, inspect for a plugged drain hose at each corner of the drainage system:

  1. Open the sunroof window.
  2. To test for blockage, pour a small container of water into the module housing drain trough. Inspect each corner to confirm the drain hose is draining water.
  3. Caution: Wear safety glasses in order to avoid eye damage.

  4. Use compressed air, 35 psi or less, to blow out any drain hose that is plugged.
  5. Test the system again.
  6. If the hose remains plugged, inspect for improper routing or kinks. Refer to Drain Hose Routing above.
  7. Remove any hoses that remain plugged. Refer to Sunroof Housing Front Drain Hose Replacement or to Sunroof Housing Rear Drain Hose Replacement .
  8. Remove the blockage:
  9. 7.1. Push a mechanics wire through the hose to remove the obstruction.
    7.2. Use compressed air in order to blow out any remaining material.
  10. Reinstall the hose. Refer to Sunroof Housing Front Drain Hose Replacement or to Sunroof Housing Rear Drain Hose Replacement .

Disconnected Drain Hose

Inspect the drainage system for disconnected drain hoses. Complete the following steps in order to obtain partial access to drain hoses and inspect for a disconnected hose.

  1. Open the sunroof window panel.
  2. Lower the headliner as needed. Refer to Headlining Trim Panel Replacement in Interior Trim.
  3. Connect any disconnected hoses.
  4. Ensure that the rear drain hoses are properly routed in the metal roof slot and attached in place.