
Black plate (21,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-21
Replacing Safety Belt
System Parts after a
Crash
{WARNING
A crash can damage the safety
belt system in the vehicle.
A damaged safety belt system
may not properly protect the
person using it, resulting in
serious injury or even death in a
crash. To help make sure the
safety belt systems are working
properly after a crash, have them
inspected and any necessary
replacements made as soon as
possible.After a minor crash, replacement of
safety belts may not be necessary.
But the safety belt assemblies that
were used during any crash may
have been stressed or damaged.
See your dealer to have the safety
belt assemblies inspected or
replaced.
New parts and repairs may be
necessary even if the safety belt
system was not being used at the
time of the crash.
Have the safety belt pretensioners
checked if the vehicle has been in a
crash, or if the airbag readiness light
stays on after you start the vehicle
or while you are driving. See
Airbag
Readiness Light on page 5‑18.
Airbag System
The vehicle has the following
airbags:
.A frontal airbag for the driver.
.A frontal airbag for the right front
passenger.
The vehicle may have the following
airbags:
.A seat‐mounted side impact
airbag for the driver.
.A seat‐mounted side impact
airbag for the right front
passenger.
.A roof-rail airbag for the driver
and the passenger seated
directly behind the driver.
.A roof-rail airbag for the right
front passenger and the person
seated directly behind the right
front passenger.

Black plate (22,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-22 Seats and Restraints
All of the airbags in the vehicle will
have the word AIRBAG embossed
in the trim or on an attached label
near the deployment opening.
For frontal airbags, the word
AIRBAG will appear on the middle
part of the steering wheel for the
driver and on the instrument panel
for the right front passenger.
With seat‐mounted side impact
airbags, the word AIRBAG will
appear on the side of the seatback
closest to the door.
With roof-rail airbags, the word
AIRBAG will appear along the
headliner or trim.
Airbags are designed to supplement
the protection provided by safety
belts. Even though today's airbags
are also designed to help reduce
the risk of injury from the force of an
inflating bag, all airbags must inflate
very quickly to do their job.Here are the most important things
to know about the airbag system:
{WARNING
You can be severely injured or
killed in a crash if you are not
wearing your safety belt
—even if
you have airbags. Airbags are
designed to work with safety
belts, but do not replace them.
Also, airbags are not designed to
deploy in every crash. In some
crashes safety belts are your only
restraint. See When Should an
Airbag Inflate? on page 3‑25.
Wearing your safety belt during a
crash helps reduce your chance
of hitting things inside the vehicle
or being ejected from it. Airbags
are “supplemental restraints” to
the safety belts. Everyone in your
vehicle should wear a safety belt
properly —whether or not there is
an airbag for that person.
{WARNING
Because airbags inflate with great
force and faster than the blink
of an eye, anyone who is up
against, or very close to any
airbag when it inflates can be
seriously injured or killed. Do not
sit unnecessarily close to any
airbag, as you would be if sitting
on the edge of the seat or leaning
forward. Safety belts help keep
you in position before and during
a crash. Always wear a safety
belt, even with airbags. The driver
should sit as far back as possible
while still maintaining control of
the vehicle.
Occupants should not lean on or
sleep against the door or side
windows in seating positions with
seat-mounted side impact airbags
and/or roof-rail airbags.

Black plate (24,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-24 Seats and Restraints
The right front passenger airbag is
in the instrument panel on the
passenger side.Driver Side Shown, PassengerSide Similar
If the vehicle has seat‐mounted side
impact airbags for the driver and
right front passenger, they are in the
side of the seatbacks closest to
the door.Driver Side Shown, Passenger Side Similar
If the vehicle has roof-rail
airbags for the driver, right front
passenger, and second row
outboard passengers, they are in
the ceiling above the side windows.

Black plate (25,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
Seats and Restraints 3-25
{WARNING
If something is between an
occupant and an airbag, the
airbag might not inflate properly
or it might force the object into
that person causing severe injury
or even death. The path of an
inflating airbag must be kept
clear. Do not put anything
between an occupant and an
airbag, and do not attach or put
anything on the steering wheel
hub or on or near any other
airbag covering.
Do not use seat accessories that
block the inflation path of a
seat-mounted side impact airbag.
Never secure anything to the roof
of a vehicle with roof-rail airbags
by routing a rope or tie‐down
through any door or window
opening. If you do, the path of an
inflating roof-rail airbag will be
blocked.
When Should an Airbag
Inflate?
Frontal airbags are designed to
inflate in moderate to severe frontal
or near-frontal crashes to help
reduce the potential for severe
injuries mainly to the driver's or right
front passenger's head and chest.
However, they are only designed
to inflate if the impact exceeds a
predetermined deployment
threshold. Deployment thresholds
are used to predict how severe a
crash is likely to be in time for the
airbags to inflate and help restrain
the occupants.
Whether the frontal airbags will
or should deploy is not based on
how fast your vehicle is traveling.
It depends largely on what you hit,
the direction of the impact, and how
quickly your vehicle slows down.Frontal airbags may inflate at
different crash speeds. For
example:.If the vehicle hits a stationary
object, the airbags could inflate
at a different crash speed than if
the vehicle hits a moving object.
.If the vehicle hits an object that
deforms, the airbags could
inflate at a different crash speed
than if the vehicle hits an object
that does not deform.
.If the vehicle hits a narrow object
(like a pole), the airbags could
inflate at a different crash speed
than if the vehicle hits a wide
object (like a wall).
.If the vehicle goes into an object
at an angle, the airbags could
inflate at a different crash speed
than if the vehicle goes straight
into the object.
Thresholds can also vary with
specific vehicle design.

Black plate (26,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-26 Seats and Restraints
Frontal airbags are not intended to
inflate during vehicle rollovers, rear
impacts, or in many side impacts.
If the GVWR (Gross Vehicle Weight
Rating) of your vehicle is 3 855 kg
(8,500 lb) or above, the vehicle has
single stage airbags. If the GVWR is
below 3 855 kg (8,500 lb) then the
vehicle has dual stage airbags.
Vehicles with a full bench seat are
equipped with single state airbags.
You can find the GVWR on the
certification label on the rear edge
of the driver door. SeeVehicle Load
Limits on page 9‑16 for more
information.
The vehicle may have dual‐stage
frontal airbags. Dual-stage airbags
adjust the restraint according to
crash severity. The vehicle has
electronic frontal sensors, which
help the sensing system distinguish
between a moderate frontal impact
and a more severe frontal impact.
For moderate frontal impacts,
dual-stage airbags inflate at a level less than full deployment. For
more severe frontal impacts, full
deployment occurs.
Vehicles with dual stage airbags
also have seat position sensors
which enable the sensing system to
monitor the position of the driver
seat (all models), and on crew cab
and extended cab models the right
front passenger seat on light duty
models only. The seat position
sensor provides information that is
used to determine if the airbags
should deploy at a reduced level or
at full deployment.
The vehicle may or may not have
seat‐mounted side impact and
roof-rail airbags. See
Airbag System
on page 3‑21. Seat‐mounted side
impact and roof-rail airbags are
intended to inflate in moderate to
severe side crashes. In addition,
these roof-rail airbags are intended
to inflate during a rollover or in a
severe frontal impact. Seat‐mounted
side impact and roof-rail airbags will
inflate if the crash severity is above the system's designed threshold
level. The threshold level can vary
with specific vehicle design.
Roof-rail airbags are not
intended to inflate in rear impacts.
A seat‐mounted side impact airbag
is intended to deploy on the side
of the vehicle that is struck. Both
roof-rail airbags will deploy when
either side of the vehicle is struck,
or if the sensing system predicts
that the vehicle is about to roll over,
or in a severe frontal impact.
In any particular crash, no one
can say whether an airbag should
have inflated simply because of the
damage to a vehicle or because
of what the repair costs were.
For frontal airbags, inflation is
determined by what the vehicle hits,
the angle of the impact, and how
quickly the vehicle slows down. For
seat‐mounted side impact and
roof-rail airbags, deployment is
determined by the location and
severity of the side impact. In a

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 (32,1)GMC Sierra Owner Manual - 2012 - CRC - 11/15/11
3-32 Seats and Restraints
Passenger Sensing
System
If the vehicle has one of the
indicators pictured in the following
illustrations, then the vehicle has a
passenger sensing system for the
right front passenger position,
unless there is an airbag off switch
located in the glove box. If there is
an airbag off switch, the vehicle
does not have a passenger sensing
system. SeeAirbag On-Off Switch
on page 3‑29 for more information.
The passenger airbag status
indicator will be visible on the
overhead console when the vehicle
is started.
In addition, if the vehicle has a
passenger sensing system for the
right front passenger position, the
label on the vehicle's sun visors
refers to “ADVANCED AIRBAGS”.
United States
Canada and Mexico
The words ON and OFF, or the
symbol for on and off, will be visible
during the system check. If you
are using remote start to start the
vehicle from a distance, if equipped,
you may not see the system
check. When the system check is
complete, either the word ON or
OFF, or the symbol for on or off, will
be visible. See Passenger Airbag
Status Indicator on page 5‑21. The passenger sensing system will
turn off the right front passenger
frontal airbag under certain
conditions. The driver airbag,
seat‐mounted side impact airbags
(if equipped), and the roof-rail
airbags (if equipped) are not
affected by the passenger sensing
system.
The passenger sensing system
works with sensors that are part
of the right front passenger seat
and safety belt. The sensors are
designed to detect the presence
of a properly-seated occupant
and determine if the right front
passenger frontal airbag should be
enabled (may inflate) or not.
According to accident statistics,
children are safer when properly
secured in a rear seat in the correct
child restraint for their weight
and size.

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.