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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
80 Seats and Restraints
Warning (Continued)
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?
This vehicle is equipped with
airbags. SeeAirbag System 077.
Airbags are designed to inflate if the
impact exceeds the specific airbag
system's 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. The vehicle has
electronic sensors which help the
airbag system determine the
severity of the impact. Deployment
thresholds can vary with specific
vehicle design.
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
front outboard passenger's head
and chest.
Whether the frontal airbags will or
should inflate is not based primarily
on how fast the vehicle is traveling. It depends on what is hit, the
direction of the impact, and how
quickly the vehicle slows down.
Frontal airbags may inflate at
different crash speeds depending on
whether the vehicle hits an object
straight on or at an angle, and
whether the object is fixed or
moving, rigid or deformable, narrow
or wide.
Frontal airbags are not intended to
inflate during vehicle rollovers, in
rear impacts, or in many side
impacts.
In addition, if the GVWR (Gross
Vehicle Weight Rating) is at or
below 3 855 kg (8,500 lb), the
vehicle has advanced technology
frontal airbags. You can find the
GVWR on the Certification/Tire label
on the center pillar of the vehicle.
See
Vehicle Load Limits 0248 for
more information.
Advanced technology frontal airbags
adjust the restraint according to
crash severity. Vehicles with
advanced technology frontal airbags
have a seat position sensor that

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Seats and Restraints 81
enables the sensing system to
monitor the position of the driver
seat. The seat position sensor
provides information that is used to
adjust the deployment of the driver
frontal airbag.
If the GVWR is at or below 4 536 kg
(10,000 lb), the vehicle has
seat-mounted side impact airbags.
Vehicles with a GVWR above
4 536 kg (10,000 lb) may or may not
have seat-mounted side impact
airbags. Seat-mounted side impact
airbags, if equipped, are designed
to inflate in moderate to severe side
crashes depending on the location
of the impact. Seat-mounted side
impact airbags are not designed to
inflate in frontal impacts, near frontal
impacts, rollovers, or rear impacts.
A seat-mounted side impact airbag
is designed to inflate on the side of
the vehicle that is struck.
Vehicles with a GVWR at or below
3 855 kg (8,500 lb) have roof-rail
airbags. These roof-rail airbags are
designed to inflate in moderate to
severe side crashes depending on
the location of the impact. Inaddition, these roof-rail airbags are
designed to inflate during a rollover
or in a severe frontal impact. The
roof-rail airbags are not designed to
inflate in rear impacts. Both roof-rail
airbags will inflate when either side
of the vehicle is struck or if the
sensing system predicts that the
vehicle is about to roll over on its
side, or in a severe frontal impact.
Vehicles with a GVWR above
3 855 kg (8,500 lb) up to and
including 4 536 kg (10,000 lb) also
have roof-rail airbags. These
roof-rail airbags are designed to
inflate in moderate to severe side
crashes depending on the location
of the impact. Both roof-rail airbags
will inflate when either side of the
vehicle is struck. In addition, these
roof-rail airbags are designed to
inflate in a severe frontal impact.
The roof-rail airbags are also
rollover capable except on models
sold as an incomplete vehicle with
the pickup box removed. If the
roof-rail airbags are rollover
capable, both roof-rail airbags will
also inflate if the sensing system
predicts that the vehicle is about toroll over on its side. The roof-rail
airbags are not designed to inflate in
rear impacts.
Vehicles with a GVWR above
4 536 kg (10,000 lb) may or may not
be equipped with roof-rail airbags.
These roof-rail airbags, if equipped,
are designed to inflate in moderate
to severe side crashes depending
on the location of the impact. Both
roof-rail airbags will inflate when
either side of the vehicle is struck.
In addition, these roof-rail airbags
are designed to inflate in a severe
frontal impact. If the vehicle has
single rear wheels and has a
factory-installed pickup box and
roof-rail airbags, the roof-rail airbags
are rollover capable. If the vehicle
has dual rear wheels, or is sold as
an incomplete vehicle, as a chassis
cab, or with the pickup box
removed, and has roof-rail airbags,
the roof-rail airbags are not rollover
capable. If the airbags are rollover
capable, both roof-rail airbags will
also inflate if the sensing system
predicts that the vehicle is about to

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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82 Seats and Restraints
roll over on its side. The roof-rail
airbags are not designed to inflate in
rear impacts.
In any particular crash, no one can
say whether an airbag should have
inflated simply because of the
vehicle damage or repair costs.
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. The inflator, the airbag,
and related hardware are all part of
the airbag module.
For airbag locations, seeWhere Are
the Airbags? 078.
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 seat belts by
distributing the force of the impact
more evenly over the
occupant's 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 of
full 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? 080.
Airbags should never be regarded
as anything more than a supplement
to seat belts.
What Will You See after
an Airbag Inflates?
For an eAssist vehicle, see the
Silverado/Sierra eAssist
supplement.
After frontal and seat-mounted side
impact airbags inflate, they quickly
deflate, so quickly that some people
may not even realize the airbags
inflated. Roof-rail airbags may still
be at least partially inflated for some
time after they inflate. Some
components of the airbag module
may be hot for several minutes. For
location of the airbags, see Where
Are the Airbags? 078.
The parts of the airbag that come
into contact with you may be warm,
but not too hot to touch. There may
be some smoke and dust coming
from the vents in the deflated
airbags. Airbag inflation does not
prevent the driver from seeing out of
the windshield or being able to steer
the vehicle, nor does it prevent
people from leaving the vehicle.

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Seats and Restraints 83
{Warning
When an airbag inflates, there
may be dust in the air. This dust
could cause breathing problems
for people with a history of
asthma or other breathing trouble.
To avoid this, everyone in the
vehicle should get out as soon as
it is safe to do so. If you have
breathing problems but cannot
get out of the vehicle after an
airbag inflates, then get fresh air
by opening a window or a door.
If you experience breathing
problems following an airbag
deployment, you should seek
medical attention.
The vehicle has a feature that may
automatically unlock the doors, turn
on the interior lamps and hazard
warning flashers, and shut off the
fuel system after the airbags inflate.
The feature may also activate,
without airbag inflation, after an
event that exceeds a predetermined
threshold. After turning the ignition off and then on again, the fuel
system will return to normal
operation; the doors can be locked,
the interior lamps can be turned off,
and the hazard warning flashers can
be turned off using the controls for
those features. If any of these
systems are damaged in the crash
they may not operate as normal.
{Warning
A crash severe enough to inflate
the airbags may have also
damaged important functions in
the vehicle, such as the fuel
system, brake and steering
systems, etc. Even if the vehicle
appears to be drivable after a
moderate crash, there may be
concealed damage that could
make it difficult to safely operate
the vehicle.
Use caution if you should attempt
to restart the engine after a crash
has occurred.
In many crashes severe enough to
inflate the airbag, windshields are
broken by vehicle deformation.
Additional windshield breakage may
also occur from the front outboard
passenger airbag.
.
Airbags are designed to inflate
only once. After an airbag
inflates, you will need some new
parts for the airbag system.
If you do not get them, the
airbag system will not be there
to help protect you in another
crash. A new system will include
airbag modules and possibly
other parts. The service manual
for the vehicle covers the need
to replace other parts.
. The vehicle has a crash sensing
and diagnostic module which
records information after a
crash. See Vehicle Data
Recording and Privacy 0477
and Event Data Recorders
0 477.
. Let only qualified technicians
work on the airbag systems.
Improper service can mean that

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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84 Seats and Restraints
an airbag system will not work
properly. See your dealer for
service.
Airbag On-Off Switch
If the passenger side instrument
panel endcap has the switch
pictured in the following illustration,
the vehicle has an airbag on-off
switch that you can use to manually
turn on or off the front outboard
passenger frontal airbag. See
Instrument Panel06.
If the vehicle does not have an
airbag on-off switch, it may have a
passenger sensing system. See
Passenger Sensing System 086. This switch should only be turned to
the off position if the person in the
front outboard passenger position is
a member of a passenger risk group
identified by the national
government as follows:
Infant. An infant (less than 1 year
old) must ride in the front seat
because:
.
My vehicle has no rear seat;
. My vehicle has a rear seat too
small to accommodate a
rear-facing infant seat; or
. The infant has a medical
condition which, according to the
infant's physician, makes it
necessary for the infant to ride in
the front seat so that the driver
can constantly monitor the
child's condition.
Child age 1 to 12. A child
age 1 to 12 must ride in the front
seat because:
. My vehicle has no rear seat;
. Although children ages 1 to 12
ride in the rear seat(s) whenever
possible, children ages 1 to 12 sometimes must ride in the front
because no space is available in
the rear seat(s) of my vehicle; or
. The child has a medical
condition which, according to the
child's physician, makes it
necessary for the child to ride in
the front seat so that the driver
can constantly monitor the
child's condition.
Medical Condition. A passenger
has a medical condition which,
according to his or her physician:
. Causes the passenger airbag to
pose a special risk for the
passenger; and
. Makes the potential harm from
the passenger airbag in a crash
greater than the potential harm
from turning off the airbag and
allowing the passenger, even if
belted, to hit the instrument
panel or windshield in a crash.

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Seats and Restraints 85
{Warning
If the front outboard passenger
frontal 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 front outboard
passenger frontal airbag unless
the person sitting there is in a risk
group.
To turn off the front outboard
passenger frontal airbag, insert the
ignition key into the switch, push in,
and move the switch to the off
position.
The word OFF or the off symbol will
come on in the passenger airbag
status indicator located in the
overhead console to let you know
that the front outboard passenger
frontal airbag is off, after the system
check is completed. The airbag off
light will come on and stay on to let
you know that the front outboard
passenger frontal airbag is off. See
Airbag On-Off Light0147. The front
outboard passenger airbag will
remain off until you turn it back on
again.
{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 front outboard
(Continued)
Warning (Continued)
passenger frontal 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. SeeAirbag Readiness
Light 0147 for more information,
including important safety
information.
To turn the front outboard passenger
frontal airbag on again, insert the
ignition key into the switch, push in,
and move the switch to the on
position.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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86 Seats and Restraints
The front outboard passenger
frontal airbag is now enabled
(may inflate). SeeAirbag On-Off
Light 0147.
Passenger Sensing
System
If the vehicle has one of the
following indicators, then the vehicle
has a passenger sensing system for
the front outboard passenger
position, unless there is an airbag
on-off switch on the instrument
panel endcap. If there is an airbag
on-off switch, the vehicle does not
have a passenger sensing system.
See Airbag On-Off Switch 084 for
more information.
The passenger airbag status
indicator will light on the overhead
console when the vehicle is started.
United States
Canada and Mexico
The words ON and OFF, or the
symbol for on and off, will be visible
during 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
0 149.
The passenger sensing system
turns off the front outboard
passenger frontal airbag under
certain conditions. No other airbag
is affected by the passenger
sensing system. The passenger sensing system
works with sensors that are part of
the front outboard passenger seat
and seat belt. The sensors are
designed to detect the presence of
a properly seated occupant and
determine if the front outboard
passenger frontal airbag should be
allowed to 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.
Whenever possible, children aged
12 and under should be secured in
a rear seating position.
Never put a rear-facing child seat in
the front. This is because the risk to
the rear-facing child is so great,
if the airbag inflates.
{Warning
A child in a rear-facing child
restraint can be seriously injured
or killed if the passenger frontal
(Continued)

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Seats and Restraints 87
Warning (Continued)
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
passenger frontal airbag inflates
and the passenger seat is in a
forward position.
Even if the passenger sensing
system has turned off the
passenger frontal airbag, no
system is fail-safe. No one can
guarantee that an airbag will not
deploy under some unusual
circumstance, even though the
airbag is turned off.
Never put a rear-facing child
restraint in the front seat, even if
the airbag is off. If securing a
forward-facing child restraint in
the front outboard passenger
seat, always move the seat as far
back as it will go. It is better to(Continued)
Warning (Continued)
secure child restraints in the rear
seat. Consider using another
vehicle to transport the child
when a rear seat is not available.
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.
The passenger sensing system is
designed to turn off the front
outboard passenger frontal airbag if:
. The front outboard passenger
seat is unoccupied.
. The system determines an infant
is present in a child restraint.
. A front outboard passenger
takes his/her weight off of the
seat for a period of time.
. There is a critical problem with
the airbag system or the
passenger sensing system. When the passenger sensing
system has turned off the front
outboard passenger frontal airbag,
the off indicator will light and stay lit
as a reminder that the airbag is off.
See
Passenger Airbag Status
Indicator 0149.
The passenger sensing system is
designed to turn on the front
outboard passenger frontal airbag
anytime the system senses that a
person of adult size is sitting
properly in the front outboard
passenger seat.
When the passenger sensing
system has allowed the airbag to be
enabled, the on indicator will light
and stay lit as a reminder that the
airbag is active.
For some children, including
children in child restraints, and for
very small adults, the passenger
sensing system may or may not turn
off the front outboard passenger
frontal airbag, depending upon the
person's seating posture and body
build. Everyone in the vehicle who
has outgrown child restraints should

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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88 Seats and Restraints
wear a seat belt properly—whether
or not there is an airbag for that
person.
{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. See Airbag Readiness
Light 0147 for more information,
including important safety
information.
If the On Indicator Is Lit for a
Child Restraint
The passenger sensing system is
designed to turn off the front
outboard passenger frontal airbag if
the system determines that an infant
is present in a child restraint. If a
child restraint has been installed
and the on indicator is lit:
1. Turn the vehicle off. 2. Remove the child restraint from
the vehicle.
3. Remove any additional items from the seat such as blankets,
cushions, seat covers, seat
heaters, or seat massagers.
4. Reinstall the child restraint following the directions
provided by the child restraint
manufacturer and refer to
Securing Child Restraints (With
the Seat Belt in the Center
Front Seat) 0114 orSecuring
Child Restraints (With the Seat
Belt in the Front Passenger
Seat) 0115 orSecuring Child
Restraints (With the Seat Belt
in the Rear Seat) 0111.
Make sure the seat belt
retractor is locked by pulling
the shoulder belt all the way
out of the retractor when
installing the child restraint,
even if the child restraint is
equipped with a seat belt lock
off. When the retractor lock is
set, the belt can be tightened
but not pulled out of the
retractor. 5. If, after reinstalling the child
restraint and restarting the
vehicle, the on indicator is still
lit, turn the vehicle off. Then
slightly recline the vehicle
seatback and adjust the seat
cushion, if adjustable, to make
sure that the vehicle seatback
is not pushing the child
restraint into the seat cushion.
Also make sure the child
restraint is not trapped under
the vehicle head restraint.
If this happens, adjust the head
restraint. See Head Restraints
0 58.
6. Restart the vehicle.
The passenger sensing system may
or may not turn off the airbag for a
child in a child restraint depending
upon the child’s size. It is better to
secure child restraints in the rear
seat. Consider using another
vehicle to transport the child when a
rear seat is not available. Never put
a rear-facing child restraint in the
front seat, even if the on indicator is
not lit.

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Seats and Restraints 89
If the Off Indicator Is Lit for an
Adult-Sized Occupant
If a person of adult size is sitting in
the front outboard passenger seat,
but the off indicator is lit, it could be
because that person is not sitting
properly in the seat or that the child
restraint locking feature is engaged.
Use the following steps to allow the
system to detect that person and
enable the front outboard passenger
frontal airbag:1. Turn the vehicle off. 2. Remove any additional material
from the seat, such as
blankets, cushions, seat
covers, seat heaters, or seat
massagers.
3. Place the seatback in the fully upright position.
4. Have the person sit upright in the seat, centered on the seat
cushion, with legs comfortably
extended.
5. If the shoulder portion of the belt is pulled out all the way,
the child restraint locking
feature will be engaged. This
may unintentionally cause the
passenger sensing system to
turn the airbag off for some
adult-sized occupants. If this
happens, unbuckle the belt, let
the belt go back all the way,
and then buckle the belt again
without pulling the belt out all
the way.
6. Restart the vehicle and have the person remain in this
position for two to three minutes
after the on indicator is lit.
{Warning
If the front outboard passenger
airbag is turned off for an
adult-sized occupant, the airbag
will not be able to inflate and help
protect that person in a crash,
resulting in an increased risk of
serious injury or even death. An
adult-sized occupant should not
ride in the front outboard
passenger seat, if the passenger
airbag off indicator is lit.
Additional Factors Affecting
System Operation
Seat belts help keep the passenger
in position on the seat during
vehicle maneuvers and braking,
which helps the passenger sensing
system maintain the passenger
airbag status. See “Seat Belts”and
“Child Restraints” in the Index for
additional information about the
importance of proper restraint use.