GMC 2009 Sierra - Manual (Page 154)

The fog lamps are cancelled after the ignition is turned
off. If you still want to use the fog lamps after the
vehicle is restarted, press the fog lamp button again.
Some localities have laws that require the headlamps to
be on along with the fog lamps.
Instrument Panel Brightness
D
(Instrument Panel Brightness): This feature
controls the brightness of the instrument panel lights
and is located next to the exterior lamp control.
Push the knob to extend out and then it can be turned.
Turn the knob clockwise or counterclockwise to brighten
or dim the instrument panel lights. Turning the knob to the
farthest clockwise position turns on the dome lamps.
Dome Lamps
The dome lamps come on when any door is opened.
They turn off after all the doors are closed.
The dome lamps can also be turned on by turning the
instrument panel brightness knob, located next to
the exterior lamps control, clockwise to the farthest
position. In this position, the dome lamps remain
on whether a door is opened or closed.
Dome Lamp Override
The dome lamp override button is located next to the
exterior lamps control.
k
(Dome Off): Press the button in and the dome
lamps remain off when a door is opened. Press
the button again to return it to the extended position so
that the dome lamps come on when a door is opened.
Entry Lighting
Your vehicle has an illuminated entry feature.
When a door is opened, the dome lamps and puddle
lamps come on if the dome override feature is not
in use. If the dome override feature is used, the lamps
do not come on.
Exit Lighting
The interior lamps come on when the key is removed
from the ignition. They turn off automatically in
20 seconds. The lights do not come on if the dome
override button is pressed in.
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