2017 GMC SIERRA 1500 ECU

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 5/3/16
52 Seats and Restraints
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) 088.
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 recline, see
Reclining
Seatbacks 053.
To adjust the lumbar support, see
Lumbar Adjustment 052.
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 0290.
Lumbar Adjustment

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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62 Seats and Restraints
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 065.
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 for
instructions on use and
important safety information.
5. To make the lap part tight, pullup on the shoulder belt.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Seats and Restraints 65
To make the belt shorter, pull its free
end as shown until the belt is snug.
If the belt is not long enough, see
Safety Belt Extender065.
Make sure the release button on the
buckle is positioned so you would
be able to unbuckle the safety belt
quickly if necessary.
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 restraints.
To wear it, attach it to the regular
safety belt. For more information,
see the instruction sheet that comes
with the extender.
Safety System Check
Check that the safety belt reminder,
safety belts, buckles, latch plates,
and retractors, are all working
properly. Look for any other loose or
damaged safety belt system parts
that might keep a safety belt system
from performing properly. See your
dealer to have it repaired. Torn or
frayed safety belts may not protect
you in a crash. They can rip apart
under impact forces. If a belt is torn
or frayed, have it replaced
immediately.
Make sure the safety belt reminder
light is working. See
Safety Belt
Reminders 0129. Keep safety belts clean and dry.
See
Safety Belt Care 065.
Safety Belt Care
Keep belts clean and dry.
{Warning
Do not bleach or dye safety belt
webbing. It may severely weaken
the webbing. In a crash, they
might not be able to provide
adequate protection. Clean and
rinse safety belt webbing only
with mild soap and lukewarm
water. Allow the webbing to dry.
Safety belts should be properly
cared for and maintained.
Safety belt hardware should be kept
dry and free of dust or debris. As
necessary exterior hard surfaces
and safety 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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 5/3/16
68 Seats and Restraints
{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 081 or
Infants and Young Children 083.
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 0130 for more
information.
Where Are the Airbags?
The driver frontal airbag is in the
center of the steering wheel.
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 5/3/16
Seats and Restraints 69
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
that person causing severe injury (Continued)
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 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 066.
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Seats and Restraints 75
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.
The front outboard passenger
frontal airbag is now enabled
(may inflate). SeeAirbag On-Off
Light 0130.
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 073 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 0132. 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 5/3/16
76 Seats and Restraints
{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
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(Continued)
Warning (Continued)
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.
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 0132.
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 5/3/16
Seats and Restraints 77
build. Everyone in the vehicle who
has outgrown child restraints should
wear a safety 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 0130 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 Safety Belt in the Center
Front Seat) 098 orSecuring
Child Restraints (With the
Safety Belt in the Rear Seat)
0 95 orSecuring Child
Restraints (With the Safety Belt
in the Front Passenger
Seat) 098.
Make sure the safety 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 safety 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 051.
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