Removal Procedure

Open the rear compartment
It is only necessary to lower the headlining trim panel. Only do those step in headlining trim panel replacement that will lower the headlining trim panel enough to gain access to the part. Refer to Headlining Trim Panel Replacement (With Sunroof) .
Remove the rear compartment side trim panel. Refer to Rear Compartment Side Trim Panel Replacement (HP6, Left Side)Rear Compartment Side Trim Panel Replacement (HP6, Right Side)Rear Compartment Side Trim Panel Replacement (without HP6) .

Fig 1: View Of Rear Sunroof Drain Hose

Courtesy of GENERAL MOTORS COMPANY

Disconnect the rear sunroof drain hose from the sunroof drain spigot.
Disengage the sunroof drain hose from the attachment clips on the roof rail, the C-pillar, and the rear compartment.

Fig 2: Identifying Rear Sunroof Drain Hose Grommet

Courtesy of GENERAL MOTORS COMPANY

Disconnect the drain hose from the grommet seated in the rear lower quarter panel.
Remove the drain hose into the passenger compartment by pulling the hose through the access hole in the rear package shelf.
If necessary, pull the grommet into the rear compartment to remove.