2019 GMC YUKON XL ECU

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-12460267) - 2019 - crc - 9/11/18
Seats and Restraints 95
Warning (Continued)
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 or console
accessories that block the
inflation path of a seat-mounted
side impact airbag or the front
center airbag, if equipped.
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 091.
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 that 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, rear
impacts, or many side impacts.
In addition, the vehicle has
advanced technology frontal
airbags. Advanced technology
frontal airbags adjust the restraint
according to crash severity.
The vehicle also has a seat position
sensor that 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.
The front center airbag, if equipped,
is designed to inflate in moderate to
severe side crashes depending

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-12460267) - 2019 - crc - 9/11/18
Seats and Restraints 99
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
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(Continued)
Warning (Continued)
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
secure child restraints in the rear
seat. Consider using another
vehicle to transport the child
when a rear seat is not available. 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 0152.
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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-12460267) - 2019 - crc - 9/11/18
100 Seats and Restraints
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
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
(Continued)
Warning (Continued)
Light0151 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)
0122 orSecuring
Child Restraints (With the Seat
Belt in the Rear Seat) 0120 or
Securing Child Restraints (With
the Seat Belt in the Front
Passenger Seat) 0123.
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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-12460267) - 2019 - crc - 9/11/18
Seats and Restraints 101
Also make sure the child
restraint is not trapped under
the vehicle head restraint.
If this happens, adjust the head
restraint. SeeHead Restraints
0 66.
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 the child restraint in a rear
seat. Never put a rear-facing child
restraint in the front seat, even if the
ON indicator is not lit.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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-12460267) - 2019 - crc - 9/11/18
Seats and Restraints 107
Warning (Continued)
Never leave children unattended
in a vehicle and never allow
children to play with the seat
belts.
Every time infants and young
children ride in vehicles, they should
have the protection provided by
appropriate child restraints. Neither
the vehicle's seat belt system nor its
airbag system is designed for them.
Children who are not restrained
properly can strike other people,
or can be thrown out of the vehicle.
{Warning
Never hold an infant or a child
while riding in a vehicle. Due to
crash forces, an infant or a child
will become so heavy it is not
possible to hold it during a crash.
For example, in a crash at only
40 km/h (25 mph), a 5.5 kg (12 lb) (Continued)
Warning (Continued)
infant will suddenly become a
110 kg (240 lb) force on a person's
arms. An infant or child should be
secured in an appropriate
restraint.
{Warning
Children who are up against,
or very close to, any airbag when
it inflates can be seriously injured(Continued)
Warning (Continued)
or killed. Never put a rear-facing
child restraint in the front
outboard seat. Secure a
rear-facing child restraint in a rear
seat. It is also better to secure a
forward-facing child restraint in a
rear seat. If you must secure a
forward-facing child restraint in
the front outboard seat, always
move the front passenger seat as
far back as it will go.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-12460267) - 2019 - crc - 9/11/18
108 Seats and Restraints
Child restraints are devices used to
restrain, seat, or position children in
the vehicle and are sometimes
called child seats or car seats.
There are three basic types of
child restraints:
.Forward-facing child restraints
. Rear-facing child restraints
. Belt-positioning booster seats
The proper child restraint for your
child depends on their size, weight,
and age, and also on whether the
child restraint is compatible with the
vehicle in which it will be used.
For each type of child restraint,
there are many different models
available. When purchasing a child
restraint, be sure it is designed to be
used in a motor vehicle. If it is, the
restraint will have a label saying that
it meets federal motor vehicle safety
standards. The restraint
manufacturer's instructions that
come with the restraint state the
weight and height limitations for a
particular child restraint. In addition, there are many kinds of restraints
available for children with special
needs.
{Warning
To reduce the risk of neck and
head injury in a crash, infants and
toddlers should be secured in a
rear-facing child restraint until age
two, or until they reach the
maximum height and weight limits
of their child restraint.
{Warning
A young child's hip bones are still
so small that the vehicle's regular
seat belt may not remain low on
the hip bones, as it should.
Instead, it may settle up around
the child's abdomen. In a crash,
the belt would apply force on a
body area that is unprotected by
any bony structure. This alone
could cause serious or fatal
(Continued)
Warning (Continued)
injuries. To reduce the risk of
serious or fatal injuries during a
crash, young children should
always be secured in appropriate
child restraints.
Child Restraint Systems
Rear-Facing Infant Restraint
A rear-facing child restraint provides
restraint with the seating surface
against the back of the infant.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-12460267) - 2019 - crc - 9/11/18
Seats and Restraints 109
The harness system holds the infant
in place and, in a crash, acts to
keep the infant positioned in the
restraint.
Forward-Facing Child Restraint
A forward-facing child restraint
provides restraint for the child's
body with the harness.
Booster Seats
A belt-positioning booster seat is
used for children who have
outgrown their forward-facing child
restraint. Boosters are designed to
improve the fit of the vehicle's seat
belt system until the child is large
enough for the vehicle seat belts to
fit properly without a booster seat.
See the seat belt fit test in Older
Children 0104.
Securing an Add-On Child
Restraint in the Vehicle
{Warning
A child can be seriously injured or
killed in a crash if the child
restraint is not properly secured in
the vehicle. Secure the child
restraint properly in the vehicle
using the vehicle’s seat belt or
LATCH system, following the
instructions that came with that
child restraint and the instructions
in this manual.
To help reduce the chance of injury,
the child restraint must be secured
in the vehicle. Child restraints must
be secured in vehicle seats by lap
belts or the lap belt portion of a
lap-shoulder belt, or by the LATCH
system. See Lower Anchors and
Tethers for Children (LATCH
System) 0111 for more information.
Children can be endangered in a
crash if the child restraint is not
properly secured in the vehicle.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-12460267) - 2019 - crc - 9/11/18
110 Seats and Restraints
When securing an add-on child
restraint, refer to the instructions
that come with the restraint which
may be on the restraint itself or in a
booklet, or both, and to this manual.
The child restraint instructions are
important, so if they are not
available, obtain a replacement
copy from the manufacturer.
Keep in mind that an unsecured
child restraint can move around in a
collision or sudden stop and injure
people in the vehicle. Be sure to
properly secure any child restraint in
the vehicle—even when no child is
in it.
In some areas of the United States
and Canada, Certified Child
Passenger Safety Technicians
(CPSTs) are available to inspect
and demonstrate how to correctly
use and install child restraints. In
the U.S., refer to the National
Highway Traffic Safety
Administration (NHTSA) website to
locate the nearest child safety seat
inspection station. For CPST availability in Canada, check with
Transport Canada or the Provincial
Ministry of Transportation office.
Securing the Child Within the
Child Restraint
{Warning
A child can be seriously injured or
killed in a crash if the child is not
properly secured in the child
restraint. Secure the child
properly following the instructions
that came with that child restraint.
Where to Put the
Restraint
According to accident statistics,
children and infants are safer when
properly restrained in an appropriate
child restraint secured in a rear
seating position.
Whenever possible, children aged
12 and under should be secured in
a rear seating position.The vehicle may be equipped with a
front center airbag in the inboard
side of the driver seat. Even with a
front center airbag, a child restraint
can be installed in any second row
seating position.
Never put a rear-facing child
restraint in the front. 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 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
front passenger airbag inflates
and the passenger seat is in a
forward position.
(Continued)