2018 GMC SIERRA DENALI warning light

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
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
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 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)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 87Warning (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 0 149 .
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/
Mexico-11349177) - 2018 - CRC - 10/17/17
88 Seats and Restraints wear a seat belt properly — whether
or not there is an airbag for that
person.
{ WarningIf 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 0 147 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) 0 114 or Securing
Child Restraints (With the Seat
Belt in the Front Passenger
Seat) 0 115 or Securing Child
Restraints (With the Seat Belt
in the Rear Seat) 0 111 .
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
92 Seats and Restraints
Replacing Airbag System
Parts after a Crash
{ WarningA crash can damage the airbag
systems in the vehicle.
A damaged airbag system may
not properly protect you and your
passenger(s) in a crash, resulting
in serious injury or even death. To
help make sure the airbag
systems are working properly
after a crash, have them
inspected and any necessary
replacements made as soon as
possible.
If an airbag inflates, you will need to
replace airbag system parts. See
your dealer for service.
If the airbag readiness light stays on
after the vehicle is started or comes
on when you are driving, the airbag
system may not work properly. Have
the vehicle serviced right away. See
Airbag Readiness Light 0 147 .Child Restraints Older Children
Older children who have outgrown
booster seats should wear the
vehicle ’ s seat belts.
The manufacturer instructions that
come with the booster seat state the
weight and height limitations for that
booster. Use a booster seat with a
lap-shoulder belt until the child
passes the fit test below: .
Sit all the way back on the seat.
Do the knees bend at the seat
edge? If yes, continue. If no,
return to the booster seat.
.
Buckle the lap-shoulder belt.
Does the shoulder belt rest on
the shoulder? If yes, continue.
If no, try using the rear seat belt
comfort guide, if available. See
“ Rear Seat Belt Comfort Guides ”
under Lap-Shoulder Belt 0 71 .
If a comfort guide is not
available, or if the shoulder belt
still does not rest on the
shoulder, then return to the
booster seat.
.
Does the lap belt fit low and
snug on the hips, touching the
thighs? If yes, continue. If no,
return to the booster seat.
.
Can proper seat belt fit be
maintained for the length of the
trip? If yes, continue. If no,
return to the booster seat.