
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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482 OnStar
security, or the operation of the
vehicle or the vehicle systems.
Software updates or changes may
affect or erase data or settings that
are stored in the vehicle, such as
saved navigation destinations or
pre-set radio stations. Neither
OnStar nor GM is responsible for
any affected or erased data or
settings. These updates or changes
may also collect personal
information. Such collection is
described in the OnStar privacy
statement or separately disclosed at
the time of installation. These
updates or changes may also cause
a system to automatically
communicate with GM servers to
collect information about vehicle
system status, identify whether
updates or changes are available,
or deliver updates or changes. An
active OnStar agreement constitutes
consent to these software updates
or changes and agreement that
either OnStar or GM may remotely
deliver them to the vehicle.Privacy
The complete OnStar Privacy
Statement may be found at
www.onstar.com (U.S.),
or www.onstar.ca (Canada). We
recommend that you review it. If you
have any questions, call
1-888-4ONSTAR (1-888-466-7827)
or press
Qto speak with an
Advisor. Users of wireless
communications are cautioned that
the privacy of any information sent
via wireless cellular communications
cannot be assured. Third parties
may unlawfully intercept or access
transmissions and private
communications without consent.
OnStar - Software
Acknowledgements
Certain OnStar components include
libcurl and unzip software and other
third party software. Below are the
notices and licenses associated with
libcurl and unzip and for other third
party software please see http://
opensource.lge.com/index
www.onstar.com/us/en/ libcurl:
COPYRIGHT AND PERMISSION
NOTICE
Copyright (c) 1996 - 2010, Daniel
Stenberg,
All rights reserved.
Permission to use, copy, modify,
and distribute this software for any
purpose with or without fee is
hereby granted, provided that the
above copyright notice and this
permission notice appear in all
copies.
THE SOFTWARE IS PROVIDED
“AS IS,”
WITHOUT WARRANTY OF
ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT
LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE
AND NONINFRINGEMENT OF
THIRD PARTY RIGHTS. IN NO
EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM,
DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF
CONTRACT, TORT OR

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Connected Services 487
vehicles, the SSID and
password can be changed in
the Wi-Fi Hotspot menu.
After initial set-up, your vehicle’s
Wi-Fi hotspot will connect
automatically to your mobile
devices. Manage data usage by
turning Wi-Fi on or off on your
mobile device, using the myGMC
mobile app, or by contacting an
OnStar Advisor. On some vehicles,
Wi-Fi can also be managed from the
Wi-Fi Hotspot menu.
MyGMC Mobile App (If Available)
Download the myGMC mobile app
to compatible Apple and Android
smartphones. GMC users can
access the following services from a
smartphone:
. Remotely start/stop the vehicle,
if factory-equipped.
. Lock/unlock doors, if equipped
with automatic locks.
. Activate the horn and lamps. .
Check the vehicle’s fuel level, oil
life, or tire pressure,
if factory-equipped with the Tire
Pressure Monitor System.
. Send destinations to the vehicle.
. Locate the vehicle on a map
(U.S. market only).
. Turn the vehicle's Wi-Fi hotspot
on/off, manage settings, and
monitor data consumption,
if equipped.
. Locate a dealer and schedule
service.
. Request roadside assistance.
. Set a parking reminder with pin
drop, take a photo, make a note,
and set a timer.
. Connect with GMC on social
media.
Features are subject to change. For
myGMC mobile app information and
compatibility, see my.gmc.com.
An active OnStar or connected
service plan may be required.
A compatible device,
factory-installed remote start, and power locks are required. Data rates
apply. See www.onstar.com for
details and system limitations.
Remote Services
Contact an OnStar Advisor to
unlock the doors or sound the horn
and flash the lamps.
Marketplace
OnStar Advisors can provide offers
from restaurants and retailers on
your route, help locate hotels,
or book a room. These services
vary by market.
Diagnostics
By monitoring and reporting on the
vehicle's key systems, OnStar
Advanced Diagnostics, if equipped,
provides a way to keep up on
maintenance. Capabilities vary by
model. See www.onstar.com for
details and system limitations.
Features are subject to change. For
updates on feature capabilities, see
my.gmc.com. Message and data
rates may apply.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
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Index 493
Glove Box . . . . . . . . . . . . . . . . . . . . . . 113
GM Mobility ReimbursementProgram . . . . . . . . . . . . . . . . . . . . . . . 466
H
Halogen Bulbs . . . . . . . . . . . . . . . . . . 367
Hazard Warning Flashers . . . . . . . 169
Head Restraints . . . . . . . . . . . . . . . . . 54
Head-up Display . . . . . . . . . . . . . . . . 152
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . 366
Automatic . . . . . . . . . . . . . . . . . . . . . 168
Bulb Replacement . . . . . . . . . . . . 367
Daytime RunningLamps (DRL) . . . . . . . . . . . . . . . . 168
Flash-to-Pass . . . . . . . . . . . . . . . . . 168
Headlamps, Front Turn Signal, Sidemarker, and
Parking Lamps . . . . . . . . . . . . . . 367
High-Beam On Light . . . . . . . . . . 147
High/Low Beam Changer . . . . . 167
Lamps On Reminder . . . . . . . . . 147
Heated Rear Seats . . . . . . . . . . . . . . . . . . . . . 64
Steering Wheel . . . . . . . . . . . . . . . 120
Heated and Ventilated Front
Seats . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Heated Mirrors . . . . . . . . . . . . . . . . . . . 44 Heater
Engine . . . . . . . . . . . . . . . . . . . . . . . . 215
Heating . . . . . . . . . . . . . . . . . . . . 177, 179
High-Beam On Light . . . . . . . . . . . . 147
High-Speed Operation . . . . . . . . . . 389
Hill and Mountain Roads . . . . . . . . 197
Hill Descent Control (HDC) . . . . . 237
Hill Descent Control Light . . . . . . . 142
Hill Start Assist (HSA) . . . . . . . . . . 235
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
How to Wear Seat Belts Properly . . . . . . . . . . . . . . . . . . . . . . . . 66
HVAC . . . . . . . . . . . . . . . . . . . . . . 177, 179
I
Ignition Positions . . . . . . . . . . 208, 210
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . . . 363
Immobilizer . . . . . . . . . . . . . . . . . . . . . . 39
Indicator Pedestrian Ahead . . . . . . . . . . . . 143
Vehicle Ahead . . . . . . . . . . . . . . . . 143
Infants and Young Children, Restraints . . . . . . . . . . . . . . . . . . . . . . 87
Information
Publication Ordering . . . . . . . . . . 472
Infotainment . . . . . . . . . . . . . . . . . . . . 176 Infotainment System . . . . . . . . . . . . 476
Instrument Cluster . . . . . . . . . . . . . . 127
Instrument Panel Overview . . . . . . . 5
Interior Rearview Mirrors . . . . . . . . . 46
Introduction . . . . . . . . . . . . . . . . . . . . . . . 2
J
Jump Starting - North
America . . . . . . . . . . . . . . . . . . . . . . . 419
K
Keyless EntryRemote (RKE) System . . . . . 13, 15
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . .9, 12
L
Labeling, Tire Sidewall . . . . . . . . . . 381
Lamps Daytime Running (DRL) . . . . . . 168
Dome . . . . . . . . . . . . . . . . . . . . . . . . . 172
Exterior Cargo . . . . . . . . . . . . . . . . 171
Exterior Controls . . . . . . . . . . . . . . 165
Exterior Lamps OffReminder . . . . . . . . . . . . . . . . . . . 167
Exterior Lighting Battery Saver . . . . . . . . . . . . . . . . . . . . . . . 174
License Plate . . . . . . . . . . . . . . . . . 369
Malfunction Indicator (Check Engine) . . . . . . . . . . . . . 138

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Index 499
Traction Control/ElectronicStability Control . . . . . . . . . . . . . . . 235
Trailer Sway Control (TSC) . . . . . . . . . . 308
Tow Mirrors . . . . . . . . . . . . . . . . . . . . . 41
Towing . . . . . . . . . . . . . . . . . . . . . . . . 292
Trailer Towing
App . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Trailering App . . . . . . . . . . . . . . . . . . 310
Transfer Case . . . . . . . . . . . . . . . . . . 227
Transmission Automatic . . . . . . . . . . . . . . . . . . . . . 221
Fluid, Automatic . . . . . . . . . . . . . . 343
Transportation Program, Courtesy . . . . . . . . . . . . . . . . . . . . . . 469
Trip Odometer . . . . . . . . . . . . . . . . . . 132
Truck-Camper Loading
Information . . . . . . . . . . . . . . . . . . . . 206
Turn and Lane-Change Signals . . . . . . . . . . . . . . . . . . . . . . . . 170
Turn Signal
Bulb Replacement . . . . . . . . . . . . 368U
Underseat Storage . . . . . . . . . . . . . 114
Uniform Tire Quality Grading . . . 401
Universal Remote System . . . . . . 161Operation . . . . . . . . . . . . . . . . . . . . . 164
Programming . . . . . . . . . . . . . . . . . 161
Using This Manual . . . . . . . . . . . . . . . . 2
V
Vehicle Alarm System . . . . . . . . . . . . . . . . . . 37
Canadian Owners . . . . . . . . . . . . . . . 2
Control . . . . . . . . . . . . . . . . . . . . . . . 188
Identification Number (VIN) . . . 458
Load Limits . . . . . . . . . . . . . . . . . . . 200
Messages . . . . . . . . . . . . . . . . . . . . 156
Personalization . . . . . . . . . . . . . . . 157
Remote Start . . . . . . . . . . . . . . . . . . . 24
Security . . . . . . . . . . . . . . . . . . . . . . . . 37
Speed Messages . . . . . . . . . . . . . 156
Towing . . . . . . . . . . . . . . . . . . . . . . . . 424
Vehicle Ahead Indicator . . . . . . . . 143
Vehicle Care Tire Pressure . . . . . . . . . . . . . . . . . 387
Vehicle Data Recording and Privacy . . . . . . . . . . . . . . . . . . . . . . . . 474
Vehicle Security Steering Column Lock . . . . . . . . . . 38 Ventilation, Air . . . . . . . . . . . . . . . . . . 182
Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Voltmeter Gauge . . . . . . . . . . . . . . . 135
W
Warning
Brake System Light . . . . . . . . . . . 140
Caution and Danger . . . . . . . . . . . . . 3
Lane Departure (LDW) . . . . . . . 276
Warning Lights, Gauges, and Indicators . . . . . . . . . . . . . . . . . . . . . 126
Warnings
Hazard Flashers . . . . . . . . . . . . . . 169
Washer Fluid . . . . . . . . . . . . . . . . . . . 354
Wheels Alignment and Tire Balance . . 403
Different Size . . . . . . . . . . . . . . . . . 401
Replacement . . . . . . . . . . . . . . . . . 403
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 398
Where to Put the Restraint . . . . . . 91
Windows . . . . . . . . . . . . . . . . . . . . . . . . 48
Manual . . . . . . . . . . . . . . . . . . . . . . . . . 49
Power . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Windshield
Replacement . . . . . . . . . . . . . . . . . 365
Wiper/Washer . . . . . . . . . . . . . . . . 120