Tahoe 2WD V8-6.0L Hybrid (2008)
Sunroof / Moonroof Drain: Procedures
Sunroof Drain Inspection and Cleaning
Drain Hose Routing
A drain trough encircles the sunroof window panel and water is drained off by the drain 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. Check to ensure the front drain hoses are routed down the windshield pillars and out the center of the pillar between the door hinges. Make sure
the hoses are not kinked.
2. Check to ensure the rear drain hoses are routed through the rear pillars and out of the rocker panel. Make sure the rear hoses are properly routed in
the metal roof slot and taped in place.
Plugged Drain Hose
If a waterleak has occurred check for a plugged drain hose at each corner of drainage system.
1. Open the sunroof window.
2. To test for blockage, pour a small container of water into the module housing drain trough. Check each corner to confirm the drain hose is draining
water.
Caution: Wear safety glasses in order to avoid eye damage.
3. Use compressed air, 241 kPa (35 psi) or less to blow out any drain hose that is plugged.
4. Test the system again.
5. If the hose remains plugged, check to see it is properly routed and does not have a kink. Refer to Drain Hose Routing.
6. Remove the blockage using the following steps.
1. Push mechanics wire through the hose to remove the obstruction.
2. Use compressed air in order to blow out any remaining material.
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 check for a
disconnected hose.
1. Open the sunroof window panel.
2. Lower the headliner as needed. Refer to Headlining Trim Panel Replacement (Avalanche/Escalade EXT w/CJ3) Headlining Trim Panel
Replacement (LWB w/CF5 w/o U42) Headlining Trim Panel Replacement (LWB w/CF5 and U42) Headlining Trim Panel Replacement (SWB
w/U42 w/o CF5) Headlining Trim Panel Replacement (SWB w/CF5 w/oU42) Headlining Trim Panel Replacement (SWB w/CJ3) Headlining
Trim Panel Replacement (LWB w/U42 w/o CF5) Headlining Trim Panel Replacement (SWB w/o CF5 and U42) Headlining Trim Panel
Replacement (Avalanche/Escalade EXT w/U42 w/o CF5) Headlining Trim Panel Replacement (Avalanche w/CJ2 w/o CF5 and U42) Headlining
Trim Panel Replacement (Avalanche/Escalade EXT w/CF5 w/o U42) Headlining Trim Panel Replacement (Avalanche/Escalade EXT w/CF5 and
U42) Headlining Trim Panel Replacement (LWB w/CJ3) Headlining Trim Panel Replacement (SWB w/CF5 and U42) Headlining Trim Panel
Replacement (LWB w/CJ2).
3. Connect any disconnected hoses.
4. Ensure that the rear drain hoses are properly routed in the metal roof slot and taped in place.
