2015 GMC SIERRA ECU

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Seats and Restraints 3-1
Seats and
Restraints
Head Restraints
Head Restraints . . . . . . . . . . . . . . . 3-2
Front Seats
Power Seat Adjustment . . . . . . . 3-3
Lumbar Adjustment . . . . . . . . . . . 3-3
Reclining Seatbacks . . . . . . . . . . 3-4
Memory Seats . . . . . . . . . . . . . . . . 3-5
Heated and Cooled FrontSeats . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Rear Seats
Rear Seats . . . . . . . . . . . . . . . . . . . . 3-9
Safety Belts
Safety Belts . . . . . . . . . . . . . . . . . . 3-10
How to Wear Safety BeltsProperly . . . . . . . . . . . . . . . . . . . . 3-11
Lap-Shoulder Belt . . . . . . . . . . . 3-12 Safety Belt Use During
Pregnancy . . . . . . . . . . . . . . . . . . 3-15
Safety Belt Extender . . . . . . . . . 3-15
Safety System Check . . . . . . . . 3-16
Safety Belt Care . . . . . . . . . . . . . 3-16
Replacing Safety Belt System Parts after a Crash . . . . . . . . . 3-16
Airbag System
Airbag System . . . . . . . . . . . . . . . 3-17
Where Are the Airbags? . . . . . 3-18
When Should an AirbagInflate? . . . . . . . . . . . . . . . . . . . . . 3-20
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . 3-22
How Does an Airbag Restrain? . . . . . . . . . . . . . . . . . . . 3-22
What Will You See after an Airbag Inflates? . . . . . . . . . . . . 3-22
Passenger Sensing System . . . . . . . . . . . . . . . . . . . . . 3-24
Servicing the Airbag-Equipped Vehicle . . . . . . . . . . . . . . . . . . . . . 3-28 Adding Equipment to the
Airbag-Equipped Vehicle . . . 3-28
Airbag System Check . . . . . . . . 3-29
Replacing Airbag System Parts after a Crash . . . . . . . . . 3-30
Child Restraints
Older Children . . . . . . . . . . . . . . . 3-30
Infants and Young
Children . . . . . . . . . . . . . . . . . . . . 3-32
Child Restraint Systems . . . . . 3-35
Where to Put the Restraint . . . 3-37
Lower Anchors and Tethers for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . 3-38
Replacing LATCH System Parts After a Crash . . . . . . . . . 3-45
Securing Child Restraints (Rear Seat) . . . . . . . . . . . . . . . . . 3-45
Securing Child Restraints (Front Passenger Seat) . . . . 3-47

Black plate (3,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Seats and Restraints 3-3
restraint and pull forward to the
desired locking position. To adjust
the head restraint rearward, grasp
the head restraint and pull forward
fully until the mechanism releases
and allows the head restraint to
return to the full rear position.
The front seat outboard head
restraints are not removable.
Rear Seats
The rear seat has adjustable
headrests in the outboard seating
positions.
The height of the headrest can be
adjusted. Pull the headrest up to
raise it. To lower the headrest, push
the headrest down.
If you are installing a child restraint
in the rear seat, see“Securing a
Child Restraint Designed for the
LATCH System” underLower
Anchors and Tethers for Children
(LATCH System) on page 3-38.
Front Seats
Power Seat Adjustment
To adjust a power seat:
.Move the seat forward or
rearward by sliding the control
forward or rearward.
.Raise or lower the front part of
the seat cushion by moving the
front of the control up or down.
.Raise or lower the seat by
moving the rear of the control up
or down. To adjust the setback, see
Reclining
Seatbacks on page 3-4.
To adjust the lumbar support, see
Lumbar Adjustment on page 3-3.
Some vehicles are equipped with a
feature that activates a vibrating
pulse alert in the driver seat to help
the driver avoid crashes. See Driver
Assistance Systems on page 9-55.
Lumbar Adjustment

Black plate (13,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Seats and Restraints 3-13
seating position, if the webbing
locks in the latch plate before it
reaches the buckle, tilt the latch
plate flat to unlock.
3. Push the latch plate into thebuckle until it clicks.
Pull up on the latch plate to
make sure it is secure. If the belt
is not long enough, see Safety
Belt Extender on page 3-15.
Position the release button on
the buckle so that the safety belt
could be quickly unbuckled if
necessary. 4. If equipped with a shoulder belt
height adjuster, move it to the
height that is right for you. See
“Shoulder Belt Height Adjuster”
later in this section.5. To make the lap part tight, pull
up on the shoulder belt.
To unlatch the belt, push the button
on the buckle. The belt should
return to its stowed position.
Before a door is closed, be sure the
safety belt is out of the way. If a
door is slammed against a safety
belt, damage can occur to both the
safety belt and the vehicle.
Shoulder Belt Height Adjuster
The vehicle has a shoulder belt
height adjuster for the driver and
front outboard passenger.

Black plate (15,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Seats and Restraints 3-15
Rear safety belt comfort guides may
provide added safety belt comfort
for older children who have
outgrown booster seats and for
some adults. When installed on a
shoulder belt, the comfort guide
positions the shoulder belt away
from the neck and head.
Adjustable comfort guides are
available through your dealer for the
rear outboard seating positions.
Instructions are included with the
guide.
Safety Belt Use During
Pregnancy
Safety belts work for everyone,
including pregnant women. Like all
occupants, they are more likely to
be seriously injured if they do not
wear safety belts.
A pregnant woman should wear a
lap-shoulder belt, and the lap
portion should be worn as low as
possible, below the rounding,
throughout the pregnancy.The best way to protect the fetus is
to protect the mother. When a safety
belt is worn properly, it is more likely
that the fetus will not be hurt in a
crash. For pregnant women, as for
anyone, the key to making safety
belts effective is wearing them
properly.
Safety Belt Extender
If the vehicle's safety belt will fasten
around you, you should use it.
But if a safety belt is not long
enough, your dealer will order you
an extender. When you go in to
order it, take the heaviest coat you
will wear, so the extender will be
long enough for you. To help avoid
personal injury, do not let someone
else use it, and use it only for the
seat it is made to fit. The extender
has been designed for adults. Never
use it for securing child seats. To
wear it, attach it to the regular safety
belt. See the instruction sheet that
comes with the extender.

Black plate (18,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
3-18 Seats and Restraints
{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.
{Warning
Children 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, seeOlder Children on
page 3-30 orInfants and Young
Children on page 3-32.
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 on page 5-16 for
more information.
Where Are the Airbags?
The driver frontal airbag is in the
center of the steering wheel.

Black plate (20,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
3-20 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 on
page 3-17. 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 on
page 9-15 for more information.
Advanced technology frontal airbags
adjust the restraint according to
crash severity. Vehicles with
advanced technology frontal airbags

Black plate (24,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
3-24 Seats and Restraints
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. SeeVehicle Data
Recording and Privacy on
page 13-14 andEvent Data
Recorders on page 13-14.
.Let only qualified technicians
work on the airbag systems.
Improper service can mean that
an airbag system will not work
properly. See your dealer for
service.
Passenger Sensing
System
The vehicle may have a passenger
sensing system for the front
outboard passenger position.
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
on page 5-17.
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 safety 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 deploys.

Black plate (25,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Seats and Restraints 3-25
{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
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
inflate under some unusual
circumstance, even though the
airbag is off.(Continued)
Warning (Continued)
Secure rear-facing child restraints
in a rear seat, even if the airbag
is off. If you secure 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 the child restraint in a
rear seat.
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 on page 5-17.
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.