
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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392 Vehicle Care
.Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly, it cannot detect or signal a
low tire pressure condition. See
your dealer for service if the TPMS
malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure.
When the low tire pressure warning
light comes on:
1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal
lamp will flash. When the recommended
pressure is reached, the horn
sounds once and the turn
signal lamp will stop flashing
and briefly turn solid.
Repeat these steps for all
underinflated tires that have
illuminated the low tire pressure
warning light.
{Warning
Overinflating a tire could cause
the tire to rupture and you or
others could be injured. Do not
exceed the maximum pressure
listed on the tire sidewall. See
Tire Sidewall Labeling 0381 and
Vehicle Load Limits 0200.
If the tire is overinflated by more
than 35 kPa (5 psi), the horn will
sound multiple times and the turn
signal lamp will continue to flash for
several seconds after filling stops.
To release and correct the pressure,
while the turn signal lamp is still
flashing, briefly press the center of the valve stem. When the
recommended pressure is reached,
the horn sounds once.
If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.
If the hazard warning flashers are
on, the tire fill alert visual feedback
will not work properly.
The TPMS will not activate the tire
fill alert properly under the following
conditions:
.
There is interference from an
external device or transmitter.
. The air pressure from the
inflation device is not sufficient
to inflate the tire.
. There is a malfunction in
the TPMS.
. There is a malfunction in the
horn or turn signal lamps.
. The identification code of the
TPMS sensor is not registered to
the system.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 395
The Trailering App can be used to
view the tire pressures after the
recommended trailer tire pressures
have been entered. Refer to the
trailer tire placard on the trailer or
the trailer tire sidewall for the
recommended tire pressure.
The system is compatible with trailer
tires that have placard pressure
values from 103 - 689 kpa (15 -
100 psi). The hole in the wheel for
the tire stem must be 11.43 mm
(0.453 in) in diameter. Use of the
pressure sensors on a wheel with a
different stem hole size could result
in loss of air from the tire.
If a low trailer tire pressure condition
is detected, the TTPMS displays a
warning message on the DIC. If the
warning message is displayed, stop
as soon as possible and inflate the
tires to the recommended pressure
shown on the tire placard on the
trailer.
In addition, the TTPMS monitors the
temperature of the trailer tires. If the
system detects a high temperature
on one or more of the trailer tires, a
warning message will be displayedon the DIC. If this warning message
is displayed, stop as soon as
possible, and inspect the
overheated trailer tire. Common
causes for high trailer tire
temperature are underinflation,
overloading, or tire damage.
TTPMS Malfunction Message
The TTPMS will not function
properly if one or more of the trailer
tire sensors are missing or
inoperable. If the system detects a
malfunction, a DIC message
indicates that the system requires
service. Some of the conditions that
can cause the service message to
occur are:
.
One of the trailer tires has been
replaced with the spare tire
which does not have a learned
TTPMS sensor. The DIC
message should turn off after the
pressure sensor is installed in
the tire, and the learning process
is performed successfully. See
"TTPMS Sensor Learning
Process" under Trailering App
0 310. .
The TTPMS sensor learning
process was not done or not
completed successfully. The DIC
message should go off after
successfully completing the
sensor learning process. See
"TTPMS Sensor Learning
Process" under Trailering App
0 310.
. One or more TTPMS sensors
are missing or damaged. The
DIC message should go off
when the TTPMS sensors are
installed and the sensor learning
process is performed
successfully. See "TTPMS
Sensor Learning Process" under
Trailering App 0310.
. Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TTPMS could cause interference
to the TTPMS which could
cause loss of signal reception
from the sensor.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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422 Vehicle Care
involved in the jump start
procedure. Put the automatic
transmission in P (Park) before
setting the parking brake. If you
have a four-wheel-drive
vehicle, be sure the transfer
case is in a drive gear, not in
N (Neutral).
Caution
If any accessories are left on or
plugged in during the jump
starting procedure, they could be
damaged. The repairs would not
be covered by the vehicle
warranty. Whenever possible, turn
off or unplug all accessories on
either vehicle when jump starting.
4. Turn the ignition off on both vehicles. Unplug unnecessary
accessories plugged into the
accessory power outlets. Turn
off the radio and all the lamps
that are not needed. This will
avoid sparks and help save
both batteries. And it could
save the radio! 5. Open the hood on the other
vehicle and locate the
positive (+) and negative (−)
terminal locations on that
vehicle.
The positive (+) terminal is
under a red plastic cover at the
positive battery post. To
uncover the positive (+)
terminal, open the red plastic
cover.
For more information on the
location of the remote
positive (+) and remote
negative (−) terminals, see
Engine Compartment Overview
0332.
{Warning
An electric fan can start up even
when the engine is not running
and can injure you. Keep hands,
clothing, and tools away from any
underhood electric fan.
{Warning
Using a match near a battery can
cause battery gas to explode.
People have been hurt doing this,
and some have been blinded.
Use a flashlight if you need more
light.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
your eyes or on your skin, flush
the place with water and get
medical help immediately.
{Warning
Fans or other moving engine
parts can injure you badly. Keep
your hands away from moving
parts once the engine is running.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 437
Cleaning High Gloss Surfaces
and Vehicle Information and
Radio Displays
Use a microfiber cloth on high gloss
surfaces or vehicle displays. First,
use a soft bristle brush to remove
dirt that can scratch the surface.
Then gently clean by rubbing with a
microfiber cloth. Never use window
cleaners or solvents. Periodically
hand wash the microfiber cloth
separately, using mild soap. Do not
use bleach or fabric softener. Rinse
thoroughly and air dry before
next use.
Caution
Do not attach a device with a
suction cup to the display. This
may cause damage and would
not be covered by the vehicle
warranty.
Instrument Panel, Leather,
Vinyl, Other Plastic Surfaces,
Low Gloss Paint Surfaces and
Natural Open Pore Wood
Surfaces
Use a soft microfiber cloth
dampened with water to remove
dust and loose dirt. For a more
thorough cleaning, use a soft
microfiber cloth dampened with a
mild soap solution.
Caution
Soaking or saturating leather,
especially perforated leather, as
well as other interior surfaces,
may cause permanent damage.(Continued)
Caution (Continued)
Wipe excess moisture from these
surfaces after cleaning and allow
them to dry naturally. Never use
heat, steam, or spot removers. Do
not use cleaners that contain
silicone or wax-based products.
Cleaners containing these
solvents can permanently change
the appearance and feel of
leather or soft trim, and are not
recommended.
Do not use cleaners that increase
gloss, especially on the instrument
panel. Reflected glare can decrease
visibility through the windshield
under certain conditions.
Caution
Use of air fresheners may cause
permanent damage to plastics
and painted surfaces. If an air
freshener comes in contact with (Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Customer Information 463
Customer
Information
Customer Information
Customer SatisfactionProcedure . . . . . . . . . . . . . . . . . . . 463
Customer Assistance Offices . . . . . . . . . . . . . . . . . . . . . . 465
Customer Assistance for Text Telephone (TTY) Users . . . . . 466
Online Owner Center . . . . . . . . . 466
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . 466
Roadside Assistance Program . . . . . . . . . . . . . . . . . . . . 467
Scheduling Service Appointments . . . . . . . . . . . . . . . 468
Courtesy Transportation Program . . . . . . . . . . . . . . . . . . . . 469
Collision Damage Repair . . . . . 470
Publication Ordering Information . . . . . . . . . . . . . . . . . . 472
Radio Frequency Statement . . . . . . . . . . . . . . . . . . . 472
Reporting Safety Defects
Reporting Safety Defects tothe United States
Government . . . . . . . . . . . . . . . . . 473
Reporting Safety Defects to the Canadian
Government . . . . . . . . . . . . . . . . . 473
Reporting Safety Defects to General Motors . . . . . . . . . . . . . 474
Vehicle Data Recording and
Privacy
Vehicle Data Recording andPrivacy . . . . . . . . . . . . . . . . . . . . . . 474
Cybersecurity . . . . . . . . . . . . . . . . . 475
Event Data Recorders . . . . . . . . 475
OnStar . . . . . . . . . . . . . . . . . . . . . . . 476
Infotainment System . . . . . . . . . . 476
Customer Information
Customer Satisfaction
Procedure
Your satisfaction and goodwill are
important to your dealer and to
GMC. Normally, any concerns with
the sales transaction or the
operation of the vehicle will be
resolved by your dealer's sales or
service departments. Sometimes,
however, despite the best intentions
of all concerned, misunderstandings
can occur. If your concern has not
been resolved to your satisfaction,
the following steps should be taken:
STEP ONE : Discuss your concern
with a member of dealership
management. Normally, concerns
can be quickly resolved at that level.
If the matter has already been
reviewed with the sales, service,
or parts manager, contact the owner
of your dealership or the general
manager.
STEP TWO : If after contacting a
member of dealership management,
it appears your concern cannot be

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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472 Customer Information
original GM parts. Remember,
recycled parts will not be covered by
the GM vehicle warranty.
Insurance pays the bill for the repair,
but you must live with the repair.
Depending on your policy limits,
your insurance company may
initially value the repair using
aftermarket parts. Discuss this with
the repair professional, and insist on
Genuine GM parts. Remember,
if the vehicle is leased, you may be
obligated to have the vehicle
repaired with Genuine GM parts,
even if your insurance coverage
does not pay the full cost.
If another party's insurance
company is paying for the repairs,
you are not obligated to accept a
repair valuation based on that
insurance company's collision policy
repair limits, as you have no
contractual limits with that company.
In such cases, you can have control
of the repair and parts choices as
long as the cost stays within
reasonable limits.Publication Ordering
Information
Service Manuals
Service manuals have the diagnosis
and repair information on the
engine, transmission, axle,
suspension, brakes, electrical
system, steering system, body, etc.
Customer Literature
Owner’s manuals are written
specifically for owners and are
intended to provide basic
operational information about the
vehicle. The owner ’s manual
includes the Maintenance Schedule
for all models.
Customer literature publications
available for purchase include
owner ’s manuals, warranty
manuals, infotainment manuals, and
portfolios. Portfolios include an
owner ’s manual, warranty manual,
infotainment manual, if applicable,
and zip lock bag or pouch.
Current and Past Models
Service manuals and customer
literature are available for many
current and past model year GM
vehicles.
To order, call 1-800-551-4123
Monday–Friday, 8:00 a.m.–6:00 p.m.
eastern time
For credit card orders only (VISA,
MasterCard, or Discover), see
Helm, Inc. at: www.helminc.com.
To order by mail, write to:
Helm, Incorporated
Attention: Customer Service
47911 Halyard Drive
Plymouth, MI 48170
Make checks payable in U.S. funds.
Radio Frequency
Statement
This vehicle has systems that
operate on a radio frequency that
complies with Part 15/Part 18 of the
Federal Communications
Commission (FCC) rules and with

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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474 Customer Information
www.tc.gc.ca/rappels (French)
or write to:
Transport Canada
Motor Vehicle Safety Directorate
Defect Investigations and
Recalls Division
80 Noel Street
Gatineau
,QC J8Z 0A1
Reporting Safety Defects
to General Motors
In addition to notifying NHTSA (or
Transport Canada) in a situation like
this, notify General Motors.
In the U.S., call 1-800-GMC-8782
(1-800-462-8782), or write:
GMC Customer Assistance Center
P.O. Box 33172
Detroit, MI 48232-5172
In Canada, call 1-800-263-3777
(English) or 1-800-263-7854
(French), or write:General Motors of Canada
Company
Customer Care Centre, Mail Code:
CA1-163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
In Mexico, call 01-800-466-0812 or
01-800-466-0801.
In other Central America and
Caribbean Countries, call
52-722-236-0680.
Vehicle Data
Recording and
Privacy
The vehicle has a number of
computers that record information
about the vehicle’s performance and
how it is driven or used. For
example, the vehicle uses computer
modules to monitor and control
engine and transmission
performance, to monitor the
conditions for airbag deployment
and deploy them in a crash, and,
if equipped, to provide antilock
braking to help the driver control the
vehicle. These modules may store
data to help the dealer technician
service the vehicle or to help GM
improve safety or features. Some
modules may also store data about
how the vehicle is operated, such as
rate of fuel consumption or average
speed. These modules may retain
personal preferences, such as radio
presets, seat positions, and
temperature settings.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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480 OnStar
.PressQto speak with an
Advisor.
OnStar or connected services
cannot work unless the vehicle is in
a place where OnStar has an
agreement with a wireless service
provider for service in that area. The
wireless service provider must also
have coverage, network capacity,
reception, and technology
compatible with OnStar or
connected services. Service
involving location information about
the vehicle cannot work unless GPS
signals are available, unobstructed,
and compatible with the OnStar
hardware. OnStar or connected
services may not work if the OnStar
equipment is not properly installed
or it has not been properly
maintained. If equipment or software
is added, connected, or modified,
OnStar or connected services may
not work. Other problems beyond
the control of OnStar —such as
hills, tall buildings, tunnels, weather,
electrical system design and
architecture of the vehicle, damage to the vehicle in a crash, or wireless
phone network congestion or
jamming
—may prevent service.
See Radio Frequency Statement
0 472.
Services for People with
Disabilities
Advisors provide services to help
with physical disabilities and
medical conditions.
Press
Qto help:
. Locate a gas station with an
attendant to pump gas.
. Find a hotel, restaurant, etc.,
that meets accessibility needs.
. Provide directions to the closest
hospital or pharmacy in urgent
situations.
TTY Users
OnStar has the ability to
communicate to deaf,
hard-of-hearing, or speech-impaired
customers while in the vehicle. The
available dealer-installed TTY
system can provide in-vehicle access to all OnStar services,
except Virtual Advisor and OnStar
Turn-by-Turn Navigation.
If equipped, TTY mode can be
turned on or off by touching
Settings, then Apps, and then
Phone. When TTY mode is on,
phone calls can be made or
received with OnStar using the
infotainment display.
OnStar Personal Identification
Number (PIN)
A PIN is needed to access some
OnStar services. The PIN will need
to be changed the first time when
speaking with an Advisor. To
change the OnStar PIN, contact an
OnStar Advisor by pressing
Qor
calling 1-888-4ONSTAR.
Warranty
OnStar equipment may be
warranted as part of the vehicle
warranty.