2012 GMC SIERRA 1500 ignition

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 (9,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Lighting 6-9
Lighting Features
Entry Lighting
The vehicle has an illuminated entry
feature.
When the doors are opened, the
dome lamps will come on if the
dome override button is in the
extended position. If the dome
override button is pressed in, the
lamps will 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.
Battery Load
Management
The vehicle has Electric Power
Management (EPM) that estimates
the battery's temperature and state
of charge. It then adjusts the voltage
for best performance and extended
life of the battery.
When the battery's state of charge
is low, the voltage is raised slightly
to quickly bring the charge back up.
When the state of charge is high,
the voltage is lowered slightly to
prevent overcharging. If the vehicle
has a voltmeter gauge or a voltage
display on the Driver Information
Center (DIC), you may see the
voltage move up or down. This is
normal. If there is a problem, an
alert will be displayed.The battery can be discharged at
idle if the electrical loads are very
high. This is true for all vehicles.
This is because the generator
(alternator) may not be spinning fast
enough at idle to produce all of
the power needed for very high
electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog
lamps, rear window defogger,
climate control fan at high speed,
heated seats, engine cooling fans,
trailer loads, and loads plugged into
accessory power outlets.
EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power whenever
needed. It can temporarily reduce
the power demands of some
accessories.

Black plate (10,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
6-10 Lighting
Normally, these actions occur in
steps or levels, without being
noticeable. In rare cases at the
highest levels of corrective action,
this action may be noticeable to the
driver. If so, a DIC message might
be displayed, such as BATTERY
SAVER ACTIVE, BATTERY
VOLTAGE LOW, or LOW BATTERY.
If one of these messages displays, it
is recommended that the driver
reduce the electrical loads as much
as possible. SeeDriver Information
Center (DIC) on page 5‑30.Battery Power Protection
This feature shuts off the dome and
reading lamps, if they are left on for
more than 10 minutes after the
ignition is turned off. The cargo
lamp shuts off after 20 minutes.
This prevents the battery from
running down.

Black plate (2,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
7-2 Infotainment System
To minimize taking your eyes off the
road while driving, do the following
while the vehicle is parked:
.Become familiar with the
operation and controls of the
audio system.
.Set up the tone, speaker
adjustments, and preset radio
stations.
For more information, see Defensive
Driving on page 9‑3. Notice:
Contact your dealer
before adding any equipment.
Adding audio or communication
equipment could interfere with
the operation of the engine, radio,
or other systems, and could
damage them. Follow federal
rules covering mobile radio and
telephone equipment.
The vehicle has Retained
Accessory Power (RAP). With RAP,
the audio system can be played
even after the ignition is turned off.
See Retained Accessory Power
(RAP) on page 9‑29 for more
information.
Navigation/Radio System
For vehicles with a navigation radio
system, see the separate Navigation
System Manual.
Theft-Deterrent Feature
TheftLock®is designed to
discourage theft of the vehicle's
radio by learning a portion of the
Vehicle Identification Number (VIN).
The radio does not operate if it is
stolen or moved to a different
vehicle.

Black plate (5,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Infotainment System 7-5
Radio with USB, CD, and DVD (MP3)
The vehicle has one of these radios
as its audio system.
Radios with CD and DVD
Vehicles with a USB, CD, and DVD
radio have a Bose®Surround
Sound System. Some of its features are explained later in this section,
“Adjusting the Speakers
(Balance/Fade).”
Vehicles with a USB, CD, and DVD
radio may have a Rear Seat
Entertainment (RSE) system. See
Rear Seat Entertainment (RSE)System on page 7‑37
for more
information on the vehicle's RSE
system.
The DVD player is the top slot
on the radio faceplate. The
player is capable of reading the
DTS‐programmed DVD Audio or
DVD Video media. (DTS and DTS
Digital Surround are registered
trademarks of Digital Theater
Systems, Inc.)
Dolby and the double-D symbol are
trademarks of Dolby Laboratories.
Manufactured under license from
Dolby Laboratories.
Using the Radio
O(Power/Volume): Press to turn
the system on and off.
Turn clockwise or counterclockwise
to increase or decrease the volume.
4(Information) (AM-FM Radio and
AM-FM Radio with CD): Press
to switch the display between the
radio station frequency and the
time. While the ignition is off, press
this button to display the time.

Black plate (16,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
7-16 Infotainment System
If the surface of a CD is soiled,
clean it with a soft, lint‐free cloth or
dampen a clean, soft cloth in a mild,
neutral detergent solution mixed
with water. Make sure the wiping
process starts from the center to
the edge.
Inserting a CD (Single CD
Player)
Insert a CD partway into the slot,
label side up. The player pulls it in
and the CD should begin playing.
Inserting a CD(s) (Six-Disc CD
Player)
LOAD^:Press to load CDs into
the CD player. This CD player holds
up to six CDs.
To insert one CD:
1. Press and release the LOAD button.
2. Wait for the message to insert the disc. 3. Load a CD. Insert the CD
partway into the slot, label side
up. The player pulls the CD in.
To insert multiple CDs:
1. Press and hold the LOAD button for two seconds. A beep sounds
and Load All Discs displays.
2. Wait for the message on when to insert the discs. The CD player
takes up to six CDs.
3. Press the LOAD button again to cancel loading more CDs.
Ejecting a CD (Single CD
Player)
ZEJECT: Press and release to
eject the disc. Remove the CD
when Remove Disc displays. If the
disc is not removed, after several
seconds the disc is automatically
pulled back into the player.
Ejecting a CD (Six-Disc CD
Player)
ZEJECT: Press and release
to eject the disc that is currently
playing. Remove the CD when
Remove Disc displays. If the disc is
not removed, after several seconds
the disc is automatically pulled back
into the player.
To eject all CDs, press and
hold the
ZEJECT button for
two seconds.
Playing a CD
If the ignition or radio is turned off
with a CD in the player, it stays in
the player. When the ignition or
radio is turned on, the CD starts
playing where it stopped, if it was
the last selected audio source. The
CD is controlled by the buttons on
the radio faceplate or by the RSA
unit. See Rear Seat Audio (RSA)
System on page 7‑46 for more
information.