
Black plate (62,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-62 Seats and Restraints
With Airbag Off Switch
This vehicle has airbags. A rear
seat is a safer place to secure a
forward-facing child restraint. See
Where to Put the Restraint on
page 3‑45.
There may be a switch in the glove
box that you can use to turn off the
right front passenger frontal airbag.
SeeAirbag On-Off Switch on
page 3‑29 for more information,
including important safety
information.
A label on the sun visor says,
“Never put a rear-facing child seat in
the front unless airbag is off.” This is
because the risk to the rear-facing
child is so great, if the airbag
deploys.{WARNING
A child in a rear-facing child
restraint can be seriously
injured or killed if the right front
passenger airbag inflates. This
is because the back of the
rear-facing child restraint would
be very close to the inflating
airbag. A child in a forward-facing
child restraint can be seriously
injured or killed if the right front
passenger airbag inflates and the
passenger seat is in a forward
position.
Even if the airbag switch has
turned off the right front
passenger frontal airbag, no
system is fail-safe. No one can
guarantee that an airbag will not
deploy under some unusual
circumstance, even though it is
turned off.
(Continued)
WARNING (Continued)
Secure rear-facing child restraints
in a rear seat, even if the
airbag is off. If you secure a
forward-facing child restraint in
the right front seat, always move
the front passenger seat as far
back as it will go. It is better to
secure the child restraint in a
rear seat.
{WARNING
If the airbag readiness light
ever comes on and stays on, it
means that something may be
wrong with the airbag system.
For example, the right front
passenger airbag could inflate
even though the airbag on-off
switch is turned off.(Continued)

Black plate (63,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-63
WARNING (Continued)
To help avoid injury to yourself or
others, have the vehicle serviced
right away. SeeAirbag Readiness
Light on page 5‑18 for more
information, including important
safety information.
If the vehicle does not have a rear
seat that will accommodate a
rear-facing child restraint, a
rear-facing child restraint should not
be installed in the vehicle, even if
the airbag is off.
If the child restraint has the
LATCH system, see Lower Anchors
and Tethers for Children (LATCH
System) on page 3‑47 for how and
where to install the child restraint
using LATCH. If a child restraint is
secured using a safety belt and it
uses a top tether, see Lower
Anchors and Tethers for Children
(LATCH System) on page 3‑47 for
top tether anchor locations. Do not secure a child restraint in a
position without a top tether anchor
if a national or local law requires
that the top tether be anchored, or if
the instructions that come with the
child restraint say that the top strap
must be anchored.
In Canada, the law requires that
forward-facing child restraints have
a top tether, and that the tether be
attached.
You will be using the lap-shoulder
belt to secure the child restraint in
this position. Follow the instructions
that came with the child restraint.
1. Move the seat as far back as it
will go before securing the
forward-facing child restraint. If you have no other choice but
to install a rear-facing child
restraint in this seat, make sure
the airbag is off once the child
restraint has been installed.
When the airbag off switch
has turned off the right front
passenger frontal airbag, the off
indicator in the airbag off light
should light and stay lit when
you start the vehicle. See
Airbag
On-Off Light on page 5‑19.
2. Put the child restraint on the seat.
3. Pick up the latch plate, and run the lap and shoulder portions of
the vehicle's safety belt through
or around the restraint. The child
restraint instructions will show
you how.

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 (10,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-10 Instruments and Controls
The accessory power outlets are
powered, even when the ignition is
in LOCK/OFF. Continuing to use
power outlets while the ignition is in
LOCK/OFF may cause the vehicle's
battery to run down.
{WARNING
Power is always supplied to the
outlets. Do not leave electrical
equipment plugged in when the
vehicle is not in use because the
vehicle could catch fire and cause
injury or death.
Notice: Leaving electrical
equipment plugged in for an
extended period of time while
the vehicle is off will drain the
battery. Always unplug electrical
equipment when not in use and
do not plug in equipment that
exceeds the maximum 20 ampere
rating. Certain power accessory plugs may
not be compatible to the accessory
power outlet and could overload
vehicle or adapter fuses. If a
problem is experienced, see your
dealer.
When adding electrical equipment,
be sure to follow the proper
installation instructions included
with the equipment. See
Add-On
Electrical Equipment on page 9‑105.
Notice: Hanging heavy
equipment from the power outlet
can cause damage not covered
by the vehicle warranty. The
power outlets are designed for
accessory power plugs only, such
as cell phone charge cords.
Cigarette Lighter
To use the cigarette lighter, push it
in all the way, and let go. When it is
ready for use, the lighter pops
back out.
Notice: Holding a cigarette lighter
in while it is heating does not let
the lighter back away from the
heating element when it is hot.
Damage from overheating can
occur to the lighter or heating
element, or a fuse could be
blown. Do not hold a cigarette
lighter in while it is heating.

Black plate (11,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Instruments and Controls 5-11
Ashtrays
The vehicle may have a front
ashtray located near the center of
the instrument panel. Pull on the
door to open it. The ashtray may
have a cigarette lighter.
Notice:If papers, pins, or other
flammable items are put in the
ashtray, hot cigarettes or other
smoking materials could ignite
them and possibly damage the
vehicle. Never put flammable
items in the ashtray.
To remove the ashtray, open the
door and pull the ashtray bin toward
you. To replace the ashtray, insert
the ashtray bin inside the ashtray
door and press down until it
engages.
Warning Lights,
Gauges, and
Indicators
Warning lights and gauges can
signal that something is wrong
before it becomes serious enough
to cause an expensive repair or
replacement. Paying attention to the
warning lights and gauges could
prevent injury.
Warning lights come on when there
could be a problem with a vehicle
function. Some warning lights come
on briefly when the engine is started
to indicate they are working. Gauges can indicate when there
could be a problem with a vehicle
function. Often gauges and warning
lights work together to indicate a
problem with the vehicle.
When one of the warning lights
comes on and stays on while
driving, or when one of the gauges
shows there may be a problem,
check the section that explains what
to do. Follow this manual's advice.
Waiting to do repairs can be costly
and even dangerous.

Black plate (18,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-18 Instruments and Controls
Passenger Safety Belt
Reminder Light
For vehicles equipped with the
passenger safety belt reminder
light, several seconds after the
engine is started, a chime sounds
for several seconds to remind the
front passenger to buckle their
safety belt. The passenger safety
belt light flashes and then stays on
solid until the belt is buckled. This
cycle continues several times if the
passenger remains or becomes
unbuckled while the vehicle is
moving.
If the passenger safety belt is
buckled, neither the chime nor the
light comes on.The front passenger safety belt
warning light and chime may turn on
if an object is put on the seat such
as a briefcase, handbag, grocery
bag, laptop, or other electronic
device. To turn off the warning light
and/or chime, remove the object
from the seat or buckle the
safety belt.Airbag Readiness Light
The system checks the airbag's
electrical system for possible
malfunctions. If the light stays on
it indicates there is an electrical
problem. The system check
includes the airbag sensor(s), the
pretensioners, the airbag modules,
the wiring, and the crash sensing
and diagnostic module. For more
information on the airbag system,
see
Airbag System on page 3‑21.
The airbag readiness light comes on
solid for a few seconds when the
engine is started. If the light does
not come on then, have it fixed
immediately.
{WARNING
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in
the vehicle might not inflate in a
crash, or they could even inflate
without a crash. To help avoid
injury, have the vehicle serviced
right away.

Black plate (20,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-20 Instruments and Controls
United States
Canada and Mexico
{WARNING
If the right front passenger airbag
is turned off for a person who is
not in a risk group identified by
the national government, that
person will not have the extra
protection of an airbag. In a
crash, the airbag will not be able
to inflate and help protect the
person sitting there.
Do not turn off the passenger
airbag unless the person sitting
there is in a risk group identified
by the national government. See
Airbag On-Off Switch on
page 3‑29for more on this,
including important safety
information.
{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. For
example, the right front
passenger airbag could inflate
even though the airbag on-off
switch is turned off.
To help avoid injury to yourself or
others, have the vehicle serviced
right away. See Airbag Readiness
Light on page 5‑18 for more
information, including important
safety information.
If the word ON or the on symbol is
lit, it means that the right front
passenger frontal airbag is enabled
(may inflate). See Airbag On-Off
Switch on page 3‑29 for more
information, including important
safety information.

Black plate (22,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
5-22 Instruments and Controls
If, after several seconds, both status
indicator lights remain on, or if there
are no lights at all, there may be a
problem with the lights or the
passenger sensing system. See
your dealer for service.
{WARNING
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong
with the airbag system. To help
avoid injury to yourself or others,
have the vehicle serviced right
away. SeeAirbag Readiness
Light on page 5‑18 for more
information, including important
safety information.
Charging System Light
This light comes on briefly when the
ignition key is turned to START, but
the engine is not running, as a
check to show it is working.
If it does not, have the vehicle
serviced by your dealer.
The light should go out once
the engine starts. If it stays on,
or comes on while driving, there
could be a problem with the
charging system. A charging system
message in the Driver Information
Center (DIC) can also appear. See
Battery Voltage and Charging
Messages on page 5‑39 for more
information. This light could indicate
that there are problems with a
generator drive belt, or that there
is an electrical problem. Have it checked right away. If the vehicle
must be driven a short distance with
the light on, turn off accessories,
such as the radio and air
conditioner.
If the vehicle is a hybrid, see the
hybrid supplement for more
information.Malfunction
Indicator Lamp
A computer system called OBD II
(On-Board Diagnostics-Second
Generation) monitors the operation
of the vehicle to ensure emissions
are at acceptable levels, to produce
a cleaner environment. This light
comes on when the vehicle is
placed in ON/RUN, as a check to
show it is working. If it does not,
have the vehicle serviced by your
dealer. See
Ignition Positions on
page 9‑26.