
Black plate (27,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-27
rollover event, roof-rail airbag
deployment is determined by the
direction of the roll.
What Makes an Airbag
Inflate?
In a deployment event, the sensing
system sends an electrical signal
triggering a release of gas from the
inflator. Gas from the inflator fills the
airbag causing the bag to break out
of the cover and deploy. The inflator,
the airbag, and related hardware are
all part of the airbag module.
Frontal airbag modules are located
inside the steering wheel and
instrument panel. For vehicles with
seat‐mounted side impact airbags,
there are airbags modules in the
side of the front seatbacks closest
to the door. For vehicles with
roof-rail airbags, there are airbag
modules in the ceiling of the vehicle,
near the side windows that have
occupant seating positions.
How Does an Airbag
Restrain?
In moderate to severe frontal or
near frontal collisions, even belted
occupants can contact the steering
wheel or the instrument panel. In
moderate to severe side collisions,
even belted occupants can contact
the inside of the vehicle.
Airbags supplement the protection
provided by safety belts. Frontal
airbags distribute the force of the
impact more evenly over the
occupant's upper body, stopping
the occupant more gradually.
Seat‐mounted side impact and
roof-rail airbags distribute the force
of the impact more evenly over the
occupant's upper body.
Rollover capable roof-rail airbags
are designed to help contain the
head and chest of occupants in the
outboard seating positions in the
first and second rows. The rollover
capable roof-rail airbags are
designed to help reduce the risk offull or partial ejection in rollover
events, although no system can
prevent all such ejections.
But airbags would not help in
many types of collisions, primarily
because the occupant's motion
is not toward those airbags. See
When Should an Airbag Inflate? on
page 3‑25
for more information.
Airbags should never be regarded
as anything more than a supplement
to safety belts.
What Will You See after
an Airbag Inflates?
After the frontal airbags and
seat-mounted side impact airbags
inflate, they quickly deflate, so
quickly that some people may not
even realize an airbag inflated.
Roof-rail airbags may still be at least
partially inflated for some time after
they deploy. Some components of
the airbag module may be hot for
several minutes. For location of the
airbag modules, see What Makes
an Airbag Inflate? on page 3‑27.

Black plate (37,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-37
WARNING (Continued)
proper service procedures, and
make sure the person performing
work for you is qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Q: Is there anything I might addto or change about the vehicle
that could keep the airbags
from working properly?
A: Yes. If you add things that
change your vehicle's frame,
bumper system, height, front end
or side sheet metal, they may
keep the airbag system from
working properly. Changing or
moving any parts of the front
seats, safety belts, the airbag
sensing and diagnostic module,
steering wheel, instrument
panel, roof-rail airbag modules,
ceiling headliner or pillar garnish
trim, overhead console, front sensors, side impact sensors,
or airbag wiring can affect the
operation of the airbag system.
In addition, the vehicle may have
a passenger sensing system
for the right front passenger's
position, which includes sensors
that are part of the passenger's
seat. The passenger sensing
system may not operate properly
if the original seat trim is
replaced with non-GM covers,
upholstery or trim, or with
GM covers, upholstery or
trim designed for a different
vehicle. Any object, such as an
aftermarket seat heater or a
comfort enhancing pad or
device, installed under or on top
of the seat fabric, could also
interfere with the operation of
the passenger sensing system.
This could either prevent proper
deployment of the passenger
airbag(s) or prevent the
passenger sensing system
from properly turning off the
passenger airbag(s). See
Passenger Sensing System on
page 3‑32.
If you have any questions
about this, you should contact
Customer Assistance before you
modify your vehicle. The phone
numbers and addresses for
Customer Assistance are in
Step Two of the Customer
Satisfaction Procedure in
this manual. See
Customer
Satisfaction Procedure (U.S.
and Canada) on page 13‑1 or
Customer Satisfaction
Procedure (Mexico) on
page 13‑3.
If the vehicle has rollover
roof-rail airbags, see Different
Size Tires and Wheels on
page 10‑70 for additional
important information.

Black plate (1,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-1
Instruments and
Controls
Controls
Steering Wheel Adjustment . . . 5-2
Steering Wheel Controls . . . . . . 5-2
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Windshield Wiper/Washer . . . . . 5-4
Compass . . . . . . . . . . . . . . . . . . . . . 5-5
Clock . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Power Outlets . . . . . . . . . . . . . . . . . 5-9
Cigarette Lighter . . . . . . . . . . . . . 5-10
Ashtrays . . . . . . . . . . . . . . . . . . . . . 5-11
Warning Lights, Gauges, and
Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . 5-11
Instrument Cluster . . . . . . . . . . . 5-12
Speedometer . . . . . . . . . . . . . . . . 5-13
Odometer . . . . . . . . . . . . . . . . . . . . 5-13
Trip Odometer . . . . . . . . . . . . . . . 5-13
Tachometer . . . . . . . . . . . . . . . . . . 5-13
Fuel Gauge . . . . . . . . . . . . . . . . . . 5-14
Engine Oil Pressure Gauge . . . . . . . . . . . . . . . . . . . . . . 5-15 Engine Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 5-16
Voltmeter Gauge . . . . . . . . . . . . . 5-16
Safety Belt Reminders . . . . . . . 5-17
Airbag Readiness Light . . . . . . 5-18
Airbag On-Off Light . . . . . . . . . . 5-19
Passenger Airbag Status Indicator . . . . . . . . . . . . . . . . . . . . 5-21
Charging System Light . . . . . . 5-22
Malfunction Indicator Lamp . . . . . . . . . . . . . 5-22
Brake System Warning Light . . . . . . . . . . . . . . . . . . . . . . . 5-25
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . 5-26
Four-Wheel-Drive Light . . . . . . 5-26
Tow/Haul Mode Light . . . . . . . . 5-26
StabiliTrak
®OFF Light . . . . . . . 5-27
Traction Control System (TCS)/StabiliTrak
®Light . . . . 5-27
Tire Pressure Light . . . . . . . . . . 5-27
Engine Oil Pressure Light . . . . 5-28
Low Fuel Warning Light . . . . . . 5-28
Security Light . . . . . . . . . . . . . . . . 5-29
High-Beam On Light . . . . . . . . . 5-29
Front Fog Lamp Light . . . . . . . . 5-29
Cruise Control Light . . . . . . . . . 5-30
Information Displays
Driver Information Center (DIC) . . . . . . . . . . . . . . . 5-30
Vehicle Messages
Vehicle Messages . . . . . . . . . . . 5-39
Battery Voltage and ChargingMessages . . . . . . . . . . . . . . . . . . 5-39
Brake System Messages . . . . 5-40
Door Ajar Messages . . . . . . . . . 5-40
Engine Cooling System Messages . . . . . . . . . . . . . . . . . . 5-41
Engine Oil Messages . . . . . . . . 5-42
Engine Power Messages . . . . 5-42
Fuel System Messages . . . . . . 5-43
Key and Lock Messages . . . . . 5-43
Lamp Messages . . . . . . . . . . . . . 5-43
Object Detection System Messages . . . . . . . . . . . . . . . . . . 5-43
Ride Control System Messages . . . . . . . . . . . . . . . . . . 5-44
Airbag System Messages . . . . 5-45
Anti-theft Alarm System Messages . . . . . . . . . . . . . . . . . . 5-45
Starting the Vehicle Messages . . . . . . . . . . . . . . . . . . 5-45
Tire Messages . . . . . . . . . . . . . . . 5-45

Black plate (2,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-2 Instruments and Controls
Transmission Messages . . . . . 5-46
Vehicle ReminderMessages . . . . . . . . . . . . . . . . . . 5-47
Washer Fluid Messages . . . . . 5-48
Vehicle Personalization
Vehicle Personalization (With DIC Buttons) . . . . . . . . . . . . . . . 5-48
Universal Remote System
Universal Remote System . . . 5-56
Universal Remote SystemProgramming . . . . . . . . . . . . . . . 5-56
Universal Remote System Operation . . . . . . . . . . . . . . . . . . 5-61
Controls
Steering Wheel
Adjustment
The tilt lever is located on the lower
left side of the steering column.
To adjust the steering wheel:
1. Hold the steering wheel and pull
the lever.
2. Move the steering wheel up or down. 3. Release the lever to lock the
wheel in place.
Do not adjust the steering wheel
while driving.
Steering Wheel Controls
If equipped, some audio controls
can be adjusted at the steering
wheel.
w(Next): Press to go to the next
favorite radio station, track on
a CD, or folder on an iPod
®or USB
device.

Black plate (4,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-4 Instruments and Controls
3. Press and release¨to move up
one track within the selected
category.
b/g(Mute/Push to Talk): Press
to silence the vehicle speakers only.
Press again to turn the sound on.
For vehicles with Bluetooth or
OnStar systems, press and hold for
longer than two seconds to interact
with those systems. See Bluetooth
on page 7‑48 andOnStar Overview
on page 14‑1 for more information.
SRCE (Source/Voice
Recognition): Press to switch
between the radio and CD, and for
equipped vehicles, the DVD, front
auxiliary, and rear auxiliary.
For vehicles with the navigation
system, press and hold this button
for longer than one second to
initiate voice recognition. See “Voice
Recognition” in the Navigation
System manual for more
information.
¨(Seek): Press to go to the
next radio station while in AM,
FM, or XM™.
For vehicles with or without a
navigation system:
Press
¨to go to the next track or
chapter while sourced to the CD or
DVD slot.
Press
¨to select a track or a folder
when navigating folders on an iPod
or USB device.
For vehicles with a navigation
system:
1. Press and hold
¨until a beep is
heard, to place the radio into
SCAN mode. A station will play
for five seconds before moving
to the next station.
2. To stop the SCAN function, press
¨again. While listening to a CD/DVD, press
and hold
¨to quickly move forward
through the tracks. Release to stop
on the desired track.
+
e: Press to increase volume.
−
e: Press to decrease volume.
Horn
To sound the horn, press the center
pad on the steering wheel.
Windshield Wiper/Washer
The front wiper control is located on
the turn and lane‐change lever.
The windshield wipers are controlled
by turning the band with
zon it.

Black plate (24,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-24 Instruments and Controls
The following may correct an
emission system malfunction:
.Check that the fuel cap is fully
installed. SeeFilling the Tank on
page 9‑72. The diagnostic
system can determine if the
fuel cap has been left off or
improperly installed. A loose or
missing fuel cap allows fuel to
evaporate into the atmosphere.
A few driving trips with the cap
properly installed should turn the
light off.
.Check that good quality fuel is
used. Poor fuel quality causes
the engine not to run as
efficiently as designed and may
cause stalling after start-up,
stalling when the vehicle is
changed into gear, misfiring,
hesitation on acceleration,
or stumbling on acceleration.
These conditions might go away
once the engine is warmed up. If one or more of these conditions
occurs, change the fuel brand used.
It will require at least one full tank of
the proper fuel to turn the light off.
See
Recommended Fuel on
page 9‑68.
If none of the above have made
the light turn off, your dealer can
check the vehicle. The dealer has
the proper test equipment and
diagnostic tools to fix any
mechanical or electrical problems
that might have developed.Emissions Inspection and
Maintenance Programs
Some local governments may have
programs to inspect the on-vehicle
emission control equipment. For
the inspection, the emission system
test equipment is connected
to the vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument
panel to the left of the steering
wheel. See your dealer if assistance
is needed.
The vehicle may not pass
inspection if:
.The malfunction indicator lamp is
on with the engine running, or if
the light does not come on when
the ignition is turned to ON/RUN
while the engine is off. See
your dealer for assistance in
verifying proper operation of the
malfunction indicator lamp.
.The OBD II (On-Board
Diagnostics) system
determines that critical
emission control systems have
not been completely diagnosed.

Black plate (26,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-26 Instruments and Controls
Antilock Brake System
(ABS) Warning Light
For vehicles with the Antilock Brake
System (ABS), this light comes on
briefly when the engine is started.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the
ignition off. If the light comes on
while driving, stop as soon as it is
safely possible and turn the ignition
off. Then start the engine again to
reset the system. If the ABS light
stays on, or comes on again while
driving, the vehicle needs service.
If the regular brake system warning
light is not on, the vehicle still has
brakes, but not antilock brakes.If the regular brake system warning
light is also on, the vehicle does not
have antilock brakes and there is a
problem with the regular brakes.
See
Brake System Warning Light on
page 5‑25.
For vehicles with a Driver
Information Center (DIC), see Brake
System Messages on page 5‑40 for
all brake‐related DIC messages.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Four-Wheel-Drive Light
For vehicles equipped with the
four-wheel-drive light, it comes on
when a vehicle with a manual transfer case is shifted into
four-wheel drive and the front axle
engages.
Some delay between the shifting
and the light coming on is normal.
See
Four-Wheel Drive on page 9‑40
for more information.
Tow/Haul Mode Light
For vehicles with the Tow/Haul
Mode feature, this light comes on
when the Tow/Haul Mode has been
activated.
For more information, see Tow/Haul
Mode on page 9‑39.

Black plate (30,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-30 Instruments and Controls
Cruise Control Light
For vehicles equipped with cruise
control, this light comes on
whenever the cruise control is set.
The light goes out when the cruise
control is turned off. SeeCruise
Control on page 9‑58 for more
information.
Information Displays
Driver Information
Center (DIC)
The vehicle has a Driver Information
Center (DIC).
The DIC displays information about
this vehicle. It also displays warning
messages if a system problem is
detected.
All messages will appear in
the DIC display located below the
tachometer in the instrument panel
cluster.
The DIC comes on when the ignition
is on. After a short delay, the DIC
will display the information that was
last displayed before the engine
was turned off. The DIC has different displays
which can be accessed by pressing
the DIC buttons located on the
instrument panel, next to the
steering wheel. If the vehicle does
not have DIC buttons, the trip
odometer reset stem can be used to
access some of the menu items.
The DIC displays trip, fuel, and
vehicle system information, and
warning messages if a system
problem is detected.
The DIC also allows some features
to be customized. See
Vehicle
Personalization (With DIC Buttons)
on page 5‑48 for more information.
If the vehicle has a diesel
engine, see the Duramax
®diesel
supplement for more information.