warning GMC SIERRA DENALI 2018 Owner's Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 69
Seat Belts This section describes how to use
seat belts properly, and some things
not to do.
{ WarningDo not let anyone ride where a
seat belt cannot be worn properly.
In a crash, if you or your
passenger(s) are not wearing
seat belts, injuries can be much
worse than if you are wearing
seat belts. You can be seriously
injured or killed by hitting things
inside the vehicle harder or by
being ejected from the vehicle. In
addition, anyone who is not
buckled up can strike other
passengers in the vehicle.
It is extremely dangerous to ride
in a cargo area, inside or outside
of a vehicle. In a collision,
passengers riding in these areas
are more likely to be seriously
injured or killed. Do not allow
(Continued) Warning (Continued) passengers to ride in any area of
the vehicle that is not equipped
with seats and seat belts.
Always wear a seat belt, and
check that all passenger(s) are
restrained properly too.
This vehicle has indicators as a
reminder to buckle the seat belts.
See Seat Belt Reminders 0 146 .
Seat Belt Assurance System This vehicle may have the Seat Belt
Assurance System, which prevents
the vehicle from shifting out of
P (Park). A message displays in the
Driver Information Center (DIC)
indicating the shift lever is locked
when the brake pedal is applied and
the seat belts for either the driver or
front outboard passenger are not
buckled. The vehicle will not shift
out of P (Park). Buckle the seat
belts to unlock the shift lever. If the front passenger seat is unoccupied,
only the driver seat belt must be
buckled to unlock the shift lever.
This system may not allow the
vehicle to shift out of P (Park) if an
object — such as a briefcase,
handbag, grocery bag, laptop,
or other electronic device — is on
the front outboard passenger seat.
If this happens, remove the object
from the seat or buckle the
seat belt.
If the driver or front outboard
passenger unbuckles their seat belt
while driving, the seat belt reminder
chime and light(s) will come on. See
Seat Belt Reminders 0 146 .
The Seat Belt Assurance System
will time out 30 seconds after the
brake pedal is initially pressed.
A message displays in the DIC
indicating the shift lever is unlocked
allowing the vehicle to be shifted out
of P (Park). See “ Seat Belts ” and
“ Child Restraints ” in the Index for
information about the importance of
proper restraint use.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 71
.
Sit up straight and always keep
your feet on the floor in front
of you.
.
Always use the correct buckle
for your seating position.
.
Wear the lap part of the belt low
and snug on the hips, just
touching the thighs. In a crash,
this applies force to the strong
pelvic bones and you would be
less likely to slide under the lap
belt. If you slid under it, the belt
would apply force on your
abdomen. This could cause
serious or even fatal injuries. .
Wear the shoulder belt over the
shoulder and across the chest.
These parts of the body are best
able to take belt restraining
forces. The shoulder belt locks if
there is a sudden stop or crash.
{ WarningYou can be seriously injured,
or even killed, by not wearing
your seat belt properly.
.
Never allow the lap or
shoulder belt to become
loose or twisted.
.
Never wear the shoulder
belt under both arms or
behind your back.
.
Never route the lap or
shoulder belt over an
armrest.
Lap-Shoulder Belt If the vehicle is a regular cab, then
all seating positions in the vehicle
have a lap-shoulder belt. If the
vehicle is a double or crew cab, then all seating positions in the
vehicle have a lap-shoulder belt
except for the center front
passenger position (if equipped),
which has a lap belt. See Lap Belt
0 75 .
The following instructions explain
how to wear a lap-shoulder belt
properly.
1. Adjust the seat, if the seat is
adjustable, so you can sit up
straight. To see how, see
“ Seats ” in the Index.
2. Pick up the latch plate and pull
the belt across you. Do not let
it get twisted.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
76 Seats and Restraints Make sure the seat belt reminder
light is working. See Seat Belt
Reminders 0 146 .
Keep seat belts clean and dry. See
Seat Belt Care 0 76 .
Seat Belt Care Keep belts clean and dry.
{ WarningDo not bleach or dye seat belt
webbing. It may severely weaken
the webbing. In a crash, they
might not be able to provide
adequate protection. Clean and
rinse seat belt webbing only with
mild soap and lukewarm water.
Allow the webbing to dry.
Seat belts should be properly cared
for and maintained.
Seat belt hardware should be kept
dry and free of dust or debris. As
necessary exterior hard surfaces
and seat belt webbing may be lightly cleaned with mild soap and water.
Ensure there is not excessive dust
or debris in the mechanism. If dust
or debris exists in the system please
see the dealer. Parts may need to
be replaced to ensure proper
functionality of the system.
Replacing Seat Belt
System Parts after a
Crash
{ WarningA crash can damage the seat belt
system in the vehicle. A damaged
seat 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 seat 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
seat belts may not be necessary.
But the seat belt assemblies that
were used during any crash may
have been stressed or damaged.
See your dealer to have the seat
belt assemblies inspected or
replaced.
New parts and repairs may be
necessary even if the seat belt
system was not being used at the
time of the crash.
Have the seat 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 0 147 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 77
Airbag System The vehicle has the following
airbags:
.
A frontal airbag for the driver
.
A frontal airbag for the front
outboard 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 front outboard
passenger
.
A roof-rail airbag for the driver
and the passenger seated
directly behind the driver
.
A roof-rail airbag for the front
outboard passenger and the
person seated directly behind
the front outboard passenger
All of the airbags in the vehicle will
have the word AIRBAG on the trim
or on a label near the deployment
opening. For frontal airbags, the word
AIRBAG is on the center of the
steering wheel for the driver and on
the instrument panel for the front
outboard passenger.
For seat-mounted side impact
airbags, the word AIRBAG is on the
seatback closest to the door.
For roof-rail airbags, the word
AIRBAG is on the ceiling or trim.
Airbags are designed to supplement
the protection provided by seat
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 seat belt, even with
airbags. Airbags are designed to
(Continued) Warning (Continued) work with seat belts, not replace
them. Also, airbags are not
designed to inflate in every crash.
In some crashes seat belts are
the only restraint. See When
Should an Airbag Inflate? 0 80 .
Wearing your seat 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 seat belts. Everyone in the
vehicle should wear a seat 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
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
78 Seats and Restraints Warning (Continued)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. Seat belts help keep you
in position before and during a
crash. Always wear a seat belt,
even with airbags. The driver
should sit as far back as possible
while still maintaining control of
the vehicle. The seat belts and
the front outboard passenger
airbags are most effective when
you are sitting well back and
upright in the seat with both feet
on the floor.
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. { WarningChildren who are up against,
or very close to, any airbag when
it inflates can be seriously injured
or killed. Always secure children
properly in the vehicle. To read
how, see Older Children 0 92 or
Infants and Young Children 0 94 .
There is an airbag readiness light
on the instrument cluster, which
shows the airbag symbol.
The system checks the airbag
electrical system for malfunctions.
The light tells you if there is an
electrical problem. See Airbag
Readiness Light 0 147 for more
information. Where Are the Airbags?
The driver frontal airbag is in the
center of the steering wheel.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 79
The front outboard passenger
frontal airbag is in the passenger
side instrument panel. Driver Side Shown, Passenger
Side Similar
If the vehicle has seat-mounted side
impact airbags for the driver and
front outboard passenger, they are
in the side of the seatbacks closest
to the door. Driver Side Crew Cab Shown,
Passenger Side Double and
Regular Cabs Similar
If the vehicle has roof-rail airbags
for the driver, front outboard
passenger, and second row
outboard passengers, they are in
the ceiling above the side windows.
{ Warning
If something is between an
occupant and an airbag, the
airbag might not inflate properly
or it might force the object into
(Continued)

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. See Airbag System 0 77 .
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 0 248 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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 83
{ WarningWhen 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.
{ WarningA 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 0 477
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/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 85
{ WarningIf 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 Light 0 147 . 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. See Airbag Readiness
Light 0 147 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/
Mexico-11349177) - 2018 - CRC - 10/17/17
86 Seats and Restraints The front outboard passenger
frontal airbag is now enabled
(may inflate). See Airbag On-Off
Light 0 147 .
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 0 84 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)