GMC Yukon Owner's Manual page 32

Sunroof
Vent: From the closed position, press the rear of the
passenger side switch to vent the sunroof.
1-26
There are two sunroof
switches located in the
overhead console above
the rearview mirror.
Manual-Open/Manual-Close: To open the sunroof,
press and hold the rear of the driver side switch until the
sunroof reaches the desired position. Press and hold
the front of the driver side switch to close it.
Express-Open/Express-Close: To express-open
the sunroof, fully press and release the rear of the
driver side switch until the sunroof reaches the desired
position. To express-close the sunroof, fully press and
release the front of the driver side switch. Press the
switch again to stop it.
The sunroof also has a sunshade that you can pull
forward to block the rays of the sun. The sunshade
must be opened and closed manually.
See Sunroof on page 3 79.