
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 5/3/16
74 Seats and Restraints
Medical Condition. A passenger
has a medical condition which,
according to his or her physician:
.Causes the passenger airbag to
pose a special risk for the
passenger; and
. Makes the potential harm from
the passenger airbag in a crash
greater than the potential harm
from turning off the airbag and
allowing the passenger, even if
belted, to hit the instrument
panel or windshield in a crash.
{Warning
If 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
(Continued)
Warning (Continued)
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
0130. 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
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 0130 for more information,
including important safety
information.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Seats and Restraints 79
A thick layer of additional material,
such as a blanket or cushion,
or aftermarket equipment such as
seat covers, seat heaters, and seat
massagers can affect how well the
passenger sensing system
operates. We recommend that you
not use seat covers or other
aftermarket equipment except when
approved by GM for your specific
vehicle. SeeAdding Equipment to
the Airbag-Equipped Vehicle 079
for more information about
modifications that can affect how
the system operates.
The on indicator may be lit if an
object, such as a briefcase,
handbag, grocery bag, laptop,
or other electronic device, is put on
an unoccupied seat. If this is not
desired, remove the object from
the seat.
{Warning
Stowing of articles under the
passenger seat or between the
passenger seat cushion and
(Continued)
Warning (Continued)
seatback may interfere with the
proper operation of the passenger
sensing system.
Servicing the
Airbag-Equipped Vehicle
Airbags affect how the vehicle
should be serviced. There are parts
of the airbag system in several
places around the vehicle. Your
dealer and the service manual have
information about servicing the
vehicle and the airbag system. To
purchase a service manual, see
Service Publications Ordering
Information0466.
{Warning
For up to 10 seconds after the
vehicle is turned off and the
battery is disconnected, an airbag
can still inflate during improper
service. You can be injured if you
(Continued)
Warning (Continued)
are close to an airbag when it
inflates. Avoid yellow connectors.
They are probably part of the
airbag system. Be sure to follow
proper service procedures, and
make sure the person performing
work for you is qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Adding accessories that change the
vehicle's frame, bumper system,
height, front end, or side sheet
metal, may keep the airbag system
from working properly. The
operation of the airbag system can
also be affected by changing any
parts of the front seats, safety belts,
the airbag sensing and diagnostic
module, steering wheel, instrument
panel, any of the airbag modules,
ceiling headliner or pillar garnish
trim, overhead console, front
sensors, side impact sensors,
or airbag wiring.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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80 Seats and Restraints
Your dealer and the service manual
have information about the location
of the airbag sensors, sensing and
diagnostic module, and airbag
wiring.
In addition, the vehicle may have a
passenger sensing system for the
front outboard passenger position,
which includes sensors that are part
of the passenger seat. The
passenger sensing system may not
operate properly if the original seat
trim is replaced with non-GM
covers, upholstery, or trim; or with
GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort-enhancing pad
or device, installed under or on top
of the seat fabric, could also
interfere with the operation of the
passenger sensing system. This
could either prevent proper
deployment of the passenger
airbag(s) or prevent the passenger
sensing system from properly
turning off the passenger airbag(s).
SeePassenger Sensing
System 075. If the vehicle has rollover roof-rail
airbags, see
Different Size Tires
and Wheels 0402 for additional
important information.
If a snow plow is added to the
vehicle, the airbags should still work
properly. The airbag systems were
designed to work properly under a
wide range of conditions, including
snow plowing with vehicles that
have the optional snow plow prep
package (RPO VYU). Do not
change or defeat the snow plow's
“tripping mechanism.” If you do, it
can damage the snow plow and the
vehicle, and may cause an airbag
deployment.
If you have to modify your vehicle
because you have a disability and
you have questions about whether
the modifications will affect the
vehicle's airbag system, or if you
have questions about whether the
airbag system will be affected if the
vehicle is modified for any other
reason, call Customer Assistance.
See Customer Assistance
Offices 0459.Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light 0130.
Caution
If an airbag covering is damaged,
opened, or broken, the airbag
may not work properly. Do not
open or break the airbag
coverings. If there are any
opened or broken airbag
coverings, have the airbag
covering and/or airbag module
replaced. For the location of the
airbags, see Where Are the
Airbags? 068. See your dealer
for service.

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Seats and Restraints 81
Replacing Airbag System
Parts after a Crash
{Warning
A 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 0130.
Child Restraints
Older Children
Older children who have outgrown
booster seats should wear the
vehicle safety 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 safety
belt comfort guide, if available.
See “Rear Safety Belt Comfort
Guides” underLap-Shoulder Belt
0 61. 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 safety belt fit be
maintained for the length of the
trip? If yes, continue. If no,
return to the booster seat.
If you have the choice, a child
should sit in a position with a
lap-shoulder belt and get the
additional restraint a shoulder
belt can provide.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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102 Seats and Restraints
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.
{Warning
A child in a rear-facing child
restraint can be seriously injured
or killed if the front outboard
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
outboard passenger airbag
inflates and the passenger seat is
in a forward position.
Even if the airbag switch has
turned off the front outboard
passenger frontal airbag, no
system is fail-safe. No one can
guarantee that an airbag will not(Continued)
Warning (Continued)
deploy under some unusual
circumstance, even though it is
turned off.
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.
{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
passenger frontal airbag could
inflate even though the airbag
on-off switch is turned off.
(Continued)
Warning (Continued)
To help avoid injury to yourself or
others, have the vehicle serviced
right away. SeeAirbag Readiness
Light 0130 for more information,
including important safety
information.
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.
If a child restraint uses a top tether,
see Lower Anchors and Tethers for
Children (LATCH System) 088 for
top tether anchor locations.
Do not secure a child restraint in a
position without a top tether anchor
if a national or local law requires
that the top tether be anchored, or if
the instructions that come with the
child restraint say that the top strap
must be anchored.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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126 Instruments and Controls
Here are four things that some
owners ask about. None of these
show a problem with the fuel gauge:
.At the service station, the fuel
pump shuts off before the gauge
reads full.
. It takes a little more or less fuel
to fill up than the gauge
indicated. For example, the
gauge may have indicated the
tank was half full, but it actually
took a little more or less than
half the tank's capacity to fill
the tank.
. The gauge moves a little while
turning a corner or speeding up.
. The gauge takes a few seconds
to stabilize after the ignition is
turned on, and goes back to
empty when the ignition is
turned off.Engine Oil Pressure
Gauge
Metric, Standard Theme Shown
English, Standard Theme Shown
The engine oil pressure gauge
shows the engine oil pressure
in kPa (kilopascals) or psi (pounds
per square inch) when the engine is
running.
Oil pressure can vary with engine
speed, outside temperature, coolant
temperature, and oil viscosity.
A reading outside the normal
operating range can be caused by a
dangerously low oil level or some
other problem causing low oil
pressure. Check the vehicle's oil as
soon as possible. See “OIL

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Instruments and Controls 127
PRESSURE LOW STOP ENGINE”
underEngine Oil Messages 0147
and Engine Oil 0348.
Caution
Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine oil
low can also damage the engine.
The repairs would not be covered
by the vehicle warranty. Check
the oil level as soon as possible.
Add oil if required, but if the oil
level is within the operating range
and the oil pressure is still low,
have the vehicle serviced. Always
follow the maintenance schedule
for changing engine oil.
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
Engine Coolant
Temperature Gauge
Metric, Standard Theme Shown
English, Standard Theme Shown
This gauge shows the engine
coolant temperature. Under normal
driving conditions the gauge will
read approximately 100 °C (210 °F)
or less. If the gauge pointer is near
125 °C (260 °F), the engine is
too hot.
It means that the engine coolant has
overheated. If the vehicle has been
operating under normal driving
conditions, pull off the road, stop the
vehicle, and turn off the engine as
soon as possible.