
Black plate (3,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Lighting 6-3
Headlamp High/
Low-Beam Changer
5 3
(Headlamp High/Low
Beam Changer): To change the
headlamps from low to high beam,
push the lever toward the instrument
panel. To return to low-beam
headlamps, pull the multifunction
lever toward you. Then release it.
When the high beams are on, this
indicator light on the instrument
panel cluster will also be on.
Flash-to-Pass
This feature lets you use the
high-beam headlamps to signal
a driver in front of you that you want
to pass. It works even if the
headlamps are in the automatic
position. To use it, pull the turn signal lever
toward you, then release it.
If the headlamps are in the
automatic position or on low
beam, the high-beam headlamps
will turn on. They will stay on as
long as you hold the lever toward
you. The high-beam indicator on the
instrument panel cluster will come
on. Release the lever to return to
normal operation.
Daytime Running
Lamps (DRL)
Daytime Running Lamps (DRL) can
make it easier for others to see the
front of your vehicle during the day.
Fully functional daytime running
lamps are required on all vehicles
first sold in Canada.
The DRL system comes on when
the following conditions are met:
.The ignition is on.
.The exterior lamps control is
in AUTO.
.The transmission is not in Park.
.The light sensor determines it is
daytime.
When the DRL system is on,
only the DRL lamps are on. The
taillamps, sidemarker, instrument
panel lights, and other lamps will not
be on.
When it begins to get dark, the
automatic headlamp system
switches from DRL to the
headlamps.
To turn off the DRL lamps, turn the
exterior lamps control to the OFF
position and then release. For
vehicles first sold in Canada, the
transmission must be in the P (Park)
position before the DRL lamps can
be turned off.

Black plate (4,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
6-4 Lighting
Automatic Headlamp
System
When it is dark enough outside, the
automatic headlamp system turns
on the headlamps at the normal
brightness, along with the taillamps,
sidemarker, parking lamps, and the
instrument panel lights. The radio
lights will also be dim.
To turn off the automatic headlamp
system, turn the exterior lamps
switch to the off position and then
release it. For vehicles first sold in
Canada, the transmission must be
in the P (Park) position before the
automatic headlamp system can be
turned off.
The vehicle has a light sensor
located on the top of the instrument
panel which regulates when the
automatic headlamps turn on. Do
not cover the sensor, otherwise the
headlamps will come on whenever
the ignition is on.
The system may also turn on the
headlamps when driving through a
parking garage or heavy overcast
weather. This is normal.
There is a delay in the transition
between the daytime and nighttime
operation of the Daytime Running
Lamps (DRL) and the automatic
headlamp systems so that driving
under bridges or bright overhead
street lights does not affect the
system. The DRL and automaticheadlamp system are only affected
when the light sensor detects a
change in lighting lasting longer
than the delay.
If the vehicle is started in a dark
garage, the automatic headlamp
system comes on immediately.
Once the vehicle leaves the garage,
it takes approximately one minute
for the automatic headlamp system
to change to DRL if it is bright
enough outside. During that delay,
the instrument panel cluster may not
be as bright as usual. Make sure the
instrument panel brightness control
is in the full bright position. See
Instrument Panel Illumination
Control on page 6‑7.
To idle the vehicle with the
automatic headlamp system off,
turn the control to the off position.
The headlamps will also stay on
after you exit the vehicle. This
feature can be programmed using
the Driver Information Center (DIC).
See
Vehicle Personalization (With
DIC Buttons) on page 5‑48.

Black plate (5,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Lighting 6-5
If the vehicle is not equipped
with DIC buttons, exit lighting is
automatic. When it is dark enough
outside, the exterior lamps remain
on for 30 seconds after the ignition
is moved from ON/RUN to
LOCK/OFF.
For vehicles without a radio, the
instrument panel light remains on for
30 seconds with the driver door
closed. For vehicles with a radio,
the instrument panel light remains
on for 10 minutes with the driver
door closed. SeeRetained
Accessory Power (RAP) on
page 9‑29.
The regular headlamp system can
be turned on when needed.Hazard Warning Flashers
|(Hazard Warning Flashers):
Press this button located on top of
the steering column, to make the
front and rear turn signal lamps
flash on and off. This warns others
that you are having trouble. Press
again to turn the flashers off.
When the hazard warning flashers
are on, the vehicle's turn signals will
not work.
Turn and Lane-Change
Signals
An arrow on the instrument panel
cluster flashes in the direction of the
turn or lane change.
Move the lever all the way up or
down to signal a turn.
Raise or lower the lever for less
than one second until the arrow
starts to flash to signal a lane
change. This causes the turn
signals to automatically flash
three times. It will flash six times
if tow-haul mode is active.

Black plate (6,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
6-6 Lighting
Holding the turn signal lever for
more than one second will cause
the turn signals to flash until you
release the lever.
The lever returns to its starting
position whenever it is released.
If after signaling a turn or a lane
change the arrows flash rapidly or
do not come on, a signal bulb could
be burned out.
Have the bulbs replaced. If the bulb
is not burned out, check the fuse.
SeeFuses and Circuit Breakers on
page 10‑44.
Turn Signal On Chime
If the turn signal is left on for more
than 1.2 km (0.75 mi), a chime will
sound at each flash of the turn
signal and the message TURN
SIGNAL ON will also appear in the
Driver Information Control (DIC). To
turn the chime and message off,
move the turn signal lever to the off
position.Fog Lamps
For vehicles with fog lamps, the
control is located next to the exterior
lamps control on the instrument
panel, to the left of the steering
column.
The ignition must be in the ON/RUN
position for the fog lamps to
come on.
#(Fog Lamps): Press to turn the
fog lamps on or off. A light will come
on in the instrument panel cluster.
When the fog lamps are turned on,
the parking lamps automatically
turn on.
When the headlamps are changed
to high beam, the fog lamps also go
off. When the high-beam headlamps
are turned off, the fog lamps will
come on again.
Some localities have laws that
require the headlamps to be on with
the fog lamps.
Auxiliary
Roof-Mounted Lamp
If the vehicle has this feature, this
button includes wiring provisions for
a dealer or a qualified service center
to install an auxiliary roof lamp.

Black plate (7,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Lighting 6-7
This button is located on the
overhead console.
When the wiring is connected to
an auxiliary roof‐mounted lamp,
pressing the bottom of the button
will activate the lamp and illuminate
an indicator light at the bottom of
this button. Pressing the top of the
button will turn off the roof‐mounted
lamp and indicator.The emergency roof lamp circuit
is fused at 30 amps, so the total
current draw of the attached lamps
should be less than this value. The
attachment points for the roof lamp
circuits are two blunt cut wires
located above the overhead
console, a dark green switched
power wire and a black ground wire.
For more information on roof mount
emergency lamp installation, please
visit the GM Upfitter website at
www.gmupfitter.com or contact your
dealer.
If the vehicle has this button,
the vehicle may have the snow
plow prep package. For further
information, see
Adding a Snow
Plow or Similar Equipment on
page 9‑106.
Interior Lighting
Instrument Panel
Illumination Control
D(Instrument Panel
Brightness): This feature controls
the brightness of the instrument
panel lights and is located next to
the exterior lamps 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.

Black plate (8,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
6-8 Lighting
Cargo Lamp
The cargo lamps come on by
turning the instrument panel
brightness control knob to the
farthest clockwise position. This
knob is located on the instrument
panel and also turns on the dome
lamps.
The cargo lamps can be used if
more light is needed in the cargo
area of the vehicle or in the top-box
storage units.
Dome Lamps
The dome lamps are located in the
overhead console.
They come on when any door is
opened and turn off after all the
doors are closed.
Turn the instrument panel
brightness knob located below
the dome lamp override button,
clockwise to the farthest position to
manually turn on the dome lamps.
The dome lamps remain on until the
knob is turned counterclockwise.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.
Reading Lamps
For vehicles with reading lamps,
they are located on the overhead
console.
To turn on the reading lamps, press
the button located next to each
lamp. To turn them off, press the
button again.
The vehicle may also have reading
lamps in other locations. To turn the
lamps on or off, press the button
located next to the lamp.
If the vehicle has a DVD Rear Seat
Entertainment (RSE) system, press
the lamp lenses to turn the lamps on
or off.
The lamps are fixed and cannot be
adjusted.

Black plate (33,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Infotainment System 7-33
player. If a portable audio player is
not connected,“No Input Device
Found” displays.
DVD/CD AUX (DVD/CD/
Auxiliary): Press to cycle through
DVD, CD, or Auxiliary when
listening to the radio. The DVD/CD
text tab and a message showing
track or chapter number will display
when a disc is in either slot. Press
again and the system automatically
searches for an auxiliary input
device, such as a portable audio
player. If a portable audio player
is not connected, “No Aux Input
Device” displays. If a disc is in
both the DVD slot and the CD slot,
the DVD/CD AUX button cycles
between the two sources and does
not indicate “No Aux Input Device.”
If a front auxiliary device is
connected, the DVD/CD AUX
button cycles through all available
options, such as: DVD slot, CD slot,
front auxiliary, and rear auxiliary
(if available). See “Using the
Auxiliary Input Jack” in this section,
or “Audio/Video (A/V) Jacks” underRear Seat Entertainment (RSE)
System on page 7‑37
for more
information.
Using the USB Port
Radios with a USB port can control
a USB storage device or an iPod®
using the radio buttons and knobs.
See “Playing an MP3” inCD Player
on page 7‑15 orCD/DVD Player on
page 7‑21 for information about how
to connect and control a USB
storage device or an iPod.
USB Support
The USB connector is located
on the instrument panel or in the
center console, and uses the
USB 2.0 standard.
USB‐Supported Devices
.USB flash drive
.Portable USB hard drive
.Fifth generation or later iPod
.iPod nano
.iPod touch
.iPod classic
Not all iPods and USB drives are
compatible with the USB port.
Make sure the iPod has the
latest firmware from Apple
®for
proper operation. iPod firmware
can be updated using the latest
iTunes
®application. See
www.apple.com/itunes.
For help with identifying the iPod, go
to www.apple.com/support.
Radios that have a USB port can
play .mp3 and .wma files that are
stored on a USB storage device as
well as AAC files that are stored on
an iPod.
USB‐Supported File and Folder
Structure
The radio supports:
.Up to 700 folders
.Up to eight folders in depth
.Up to 65,535 files.

Black plate (34,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
7-34 Infotainment System
.Folder and file names up to
64 bytes
.Files with an .mp3 or .wma file
extension
.AAC files stored on an iPod
.FAT16
.FAT32
Connecting a USB Storage
Device or iPod®
The USB port can be used to
control an iPod or a USB storage
device.
To connect a USB storage device,
connect the device to the USB port
located in the center console or on
the instrument panel.
To connect an iPod, connect one
end of the USB cable that came
with the iPod to the iPod’s dock
connector and connect the other
end to the USB port located in the
center console or on the instrument
panel. If the vehicle is on and the
USB connection works,“OK to
disconnect” and a GM logo may appear on the iPod, and iPod
appears on the radio display. The
iPod music appears on the radio’s
display and begins playing.
The iPod charges while it is
connected to the vehicle if the
vehicle is in the ACC/ACCESSORY
or ON/RUN position. When the
vehicle is turned off, the iPod
automatically powers off and will
not charge or draw power from the
vehicle's battery.
If you have an older iPod model that
is not supported, it can still be used
by connecting it to the auxiliary
input jack using a standard 3.5 mm
(1/8 in) stereo cable. See
“Using the
Auxiliary Input Jack” earlier for more
information.
Using the Radio to Control a
USB Storage Device or iPod
The radio can control a USB
storage device or an iPod using
the radio buttons and knobs, and
display song information on the
radio’s display.
f(Tune): Turn to select files.
©SEEK:Press to go to the start of
the track, if more than 10 seconds
have played. Press and hold or
press multiple times to continue
moving backward through tracks.
¨SEEK: Press to go to the next
track. Press and hold or press
multiple times to continue moving
forward through tracks.
sREV (Reverse): Press and hold
to reverse playback quickly. Sound
is heard at a reduced volume.
Release
sREV to resume playing.
The elapsed time of the file
displays.
\FWD (Fast Forward): Press
and hold to advance playback
quickly. Sound is heard at a reduced
volume. Release
\FWD to
resume playing. The elapsed time of
the file displays.
4(Information): Press to display
additional information about the
selected track.