GMC 2012 Sierra - Manual (Page 63)

Black plate (19,1) GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Keys, Doors, and Windows 2-19
Windows
{
WARNING
Leaving children, helpless adults,
or pets in a vehicle with the
windows closed is dangerous.
They can be overcome by the
extreme heat and suffer
permanent injuries or even death
from heat stroke. Never leave a
child, a helpless adult, or a pet
alone in a vehicle, especially with
the windows closed in warm or
hot weather.
The vehicle aerodynamics are
designed to improve fuel economy
performance. This may result in a
pulsing sound when a window is
partially open. To reduce the sound,
open another window or the sunroof
(if equipped).
Manual Windows
Turn the hand crank on each door
to manually raise or lower the
manual windows.