onstar GMC SIERRA 2021 Owner's Manual

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 2/18/21
Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Keys, Doors, and Windows . . . . . . . . . . . . . . . 7
Seats and Restraints . . . . . . . . . . . . . . . . . . . . . 45
Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Instruments and Controls . . . . . . . . . . . . . . . 99
Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Infotainment System . . . . . . . . . . . . . . . . . . . 148
Climate Controls . . . . . . . . . . . . . . . . . . . . . . . 204
Driving and Operating . . . . . . . . . . . . . . . . . . 211
Vehicle Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
Service and Maintenance . . . . . . . . . . . . . . 408
Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . 423
Customer Information . . . . . . . . . . . . . . . . . . 428
Reporting Safety Defects . . . . . . . . . . . . . . . 436
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 440
Connected Services . . . . . . . . . . . . . . . . . . . . . 445
Index . . . . . . . . . . . . . . . . . . . . . . . . . . 448
Introduction
The names, logos, emblems, slogans, vehicle
model names, and vehicle body designs
appearing in this manual including, but not
limited to, GM, the GM logo, GMC, the GMC
Truck Emblem, SIERRA, and DENALI are
trademarks and/or service marks of General
Motors LLC, its subsidiaries, affiliates,
or licensors.
For vehicles first sold in Canada, substitute
the name“General Motors of Canada
Company” for GMC Division wherever it
appears in this manual. This manual describes features that may or
may not be on the vehicle because of
optional equipment that was not purchased
on the vehicle, model variants, country
specifications, features/applications that may
not be available in your region, or changes
subsequent to the printing of this owner’s
manual.
If the vehicle has the Duramax diesel
engine, see the Duramax diesel supplement
for additional and specific information on
this engine.
Refer to the purchase documentation
relating to your specific vehicle to confirm
the features.
Keep this manual in the vehicle for quick
reference.
Litho in U.S.A.
Part No. 84550392 C Third Printing©2021 General Motors LLC. All Rights Reserved.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Keys, Doors, and Windows 9
Programming Keys
Follow these procedures to program up to
eight keys to the vehicle.
Programming with Two Recognized Keys
To program a new key:1. Insert the original, already programmed key in the ignition and turn the
ignition on.
2. Turn the ignition off, and remove the key.
3. Quickly, within five seconds, insert the second original already programmed key
in the ignition and turn the ignition on.
4. Turn the ignition off, and remove the key.
5. Insert the key to be programmed and turn the ignition on within five seconds.
6. After a few seconds, the security light will turn off once the key has been
programmed.
7. Repeat Steps 1–5 if additional keys are to be programmed.
If a key is lost or damaged, see your dealer
to have a new key made. Programming without Recognized Keys
Program a new key to the vehicle when a
recognized key is not available. Canadian
regulations require that owners see their
dealer.
If two currently recognized keys are not
available, follow this procedure to program
the first key.
This procedure will take approximately
30 minutes to complete for the first key.
The vehicle must be off and all of the keys
you wish to program must be with you.
1. Insert the new vehicle key into the ignition.
2. Turn the ignition on. The security light will come on.
3. Wait 10 minutes until the security light turns off.
4. Turn the ignition off.
5. Repeat Steps 2–4 two more times. After the third time, turn the ignition on; the
key is learned and all previously known
keys will no longer work with the
vehicle.
6. To learn a second key, turn the ignition off, insert the second key to be learned,
and turn the ignition on. After two keys are learned, the remaining
keys can be learned by following the
procedure in
“Programming with Two
Recognized Keys.”
The key has a bar-coded key tag that the
dealer or qualified locksmith can use to
make new keys. Store this information in a
safe place, not in the vehicle.
See your dealer if a replacement key or
additional key is needed.
If it becomes difficult to turn a key, inspect
the key blade for debris. Periodically clean
with a brush or pick.
If locked out of the vehicle, see Roadside
Assistance Program 0431.
With an active OnStar or connected service
plan, an OnStar Advisor may remotely
unlock the vehicle. See OnStar Overview
0 440.
Keys (Keyless Access)
{Warning
Leaving children in a vehicle with an
ignition key or Remote Keyless Entry
(RKE) transmitter is dangerous and
(Continued)

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10 Keys, Doors, and Windows
Warning (Continued)
children or others could be seriously
injured or killed. They could operate the
power window or other controls or make
the vehicle move. The windows will
function with the key in the ignition or
with the RKE transmitter in the vehicle,
and children or others could be caught in
the path of a closing window. Do not
leave children in a vehicle with the
ignition key or an RKE transmitter.
If the vehicle has the Keyless Access system,
the transmitter has a button on the side of
the transmitter used to remove the key.This key is used for the driver door and
glove box.
Press the button to remove the key. Never
pull the key out without pressing the
button.
See your dealer if a replacement key or
additional key is needed.
If it becomes difficult to turn a key, inspect
the key blade for debris. Periodically clean
with a brush or pick.
With an active OnStar or connected service
plan, an OnStar Advisor may remotely
unlock the vehicle. See
OnStar Overview
0 440. If locked out of the vehicle, see
Roadside
Assistance Program 0431.
If equipped with memory seats, RKE
transmitters 1 and 2 are linked to seating
positions of memory 1 or 2. See Memory
Seats 049.
Remote Keyless Entry (RKE)
System
See Radio Frequency Statement 0436.
If there is a decrease in the Remote Keyless
Entry (RKE) operating range:
.Check the distance. The transmitter may
be too far from the vehicle.
.Check the location. Other vehicles or
objects may be blocking the signal.
.Check the transmitter's battery. See
“Battery Replacement” later in this
section.
.If the transmitter is still not working
correctly, see your dealer or a qualified
technician for service.
Remote Keyless Entry (RKE)
System Operation (Key Access)
The RKE transmitter functions may work up
to 60 m (197 ft) away from the vehicle.

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130 Instruments and Controls
Navigation/Active OnStar View :This
displays the speed view along with
indicators for vehicle ahead, Lane Departure
Warning/Lane Keep Assist, trailer sway, and
pedestrian advisory. Turn-by-Turn navigation
information is shown during active route.
The compass heading is displayed when
navigation routing is not active.
Navigation Turn-by-Turn Alerts shown in the
instrument cluster may also be displayed in
any HUD view.
English Shown, Metric Similar
Off Road View : This displays the speed
view along with indicators for vehicle ahead,
Lane Departure Warning/Lane Keep Assist,
trailer sway, four-wheel drive status, and
pedestrian advisory. Off-road information
such as pitch angle, steering angle, and
rolling angle is also shown.
Care of the HUD
Clean the inside of the windshield to remove
any dirt or film that could reduce the
sharpness or clarity of the HUD image.
Clean the HUD lens with a soft cloth
sprayed with glass cleaner. Wipe the lens
gently, then dry it.
HUD Troubleshooting
Check that:
.Nothing is covering the HUD lens.
.The HUD brightness setting is not too
dim or too bright.
.The HUD is adjusted to the proper height.
.Polarized sunglasses are not worn.
.The windshield and HUD lens are clean.
If the HUD image is not correct, contact
your dealer.
The windshield is part of the HUD system.
See Windshield Replacement 0348.
Vehicle Messages
Messages displayed on the Driver
Information Center (DIC) indicate the status
of the vehicle or some action that may be
needed to correct a condition. Multiple
messages may appear one after another.
The messages that do not require
immediate action can be acknowledged and
cleared by pressing the thumbwheel. The
messages that require immediate action
cannot be cleared until that action is
performed.
All messages should be taken seriously;
clearing the message does not correct the
problem.
If a SERVICE message appears, see your
dealer.
Follow the instructions given in the
messages. The system displays messages
regarding the following topics:
.Service Messages
.Fluid Levels
.Vehicle Security
.Brakes
.Steering
.Ride Control Systems

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148 Infotainment System
Infotainment System
Introduction
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Steering Wheel Controls . . . . . . . . . . . . . . . 151
Using the System . . . . . . . . . . . . . . . . . . . . . . 152
Software Updates . . . . . . . . . . . . . . . . . . . . . . 155
Radio
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . . . . 155
HD Radio Technology . . . . . . . . . . . . . . . . . . 156
Radio Data System (RDS) . . . . . . . . . . . . . . 157
Satellite Radio . . . . . . . . . . . . . . . . . . . . . . . . . 157
Radio Reception . . . . . . . . . . . . . . . . . . . . . . . 158
Fixed Mast Antenna . . . . . . . . . . . . . . . . . . . 158
Multi-Band Antenna . . . . . . . . . . . . . . . . . . . 158
Audio Players
Avoiding Untrusted Media Devices . . . . . 158
USB Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Auxiliary Jack . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Bluetooth Audio . . . . . . . . . . . . . . . . . . . . . . . 162
OnStar System
OnStar System . . . . . . . . . . . . . . . . . . . . . . . . 162
Navigation
Using the Navigation System . . . . . . . . . . 163
Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
Navigation Symbols . . . . . . . . . . . . . . . . . . . 166Destination . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
OnStar System . . . . . . . . . . . . . . . . . . . . . . . . . 173
Global Positioning System (GPS) . . . . . . . 173
Vehicle Positioning . . . . . . . . . . . . . . . . . . . . 174
Problems with Route Guidance . . . . . . . . 174
If the System Needs Service . . . . . . . . . . . 175
Map Data Updates . . . . . . . . . . . . . . . . . . . . . 175
Database Coverage Explanations . . . . . . . 175
Voice Recognition
Voice Recognition . . . . . . . . . . . . . . . . . . . . . . 175
Phone
Bluetooth (Overview) . . . . . . . . . . . . . . . . . . 180
Bluetooth (Pairing and Using a
Phone) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
Apple CarPlay and Android Auto . . . . . . . 185
Settings
Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186
Teen Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
Trademarks and License Agreements
Trademarks and License Agreements . . . . . . . . . . . . . . . . . . . . . . . . . . 195
Introduction
Read the following pages to become familiar
with the features.
{Warning
Taking your eyes off the road for too
long or too often while using any
infotainment feature can cause a crash.
You or others could be injured or killed.
Do not give extended attention to
infotainment tasks while driving. Limit
your glances at the vehicle displays and
focus your attention on driving. Use voice
commands whenever possible.
The infotainment system has built-in
features intended to help avoid distraction
by disabling some features when driving.
These features may gray out when they are
unavailable. Many infotainment features are
also available through the instrument cluster
and steering wheel controls.
Before driving:
.Become familiar with the operation,
center stack controls, steering wheel
controls, and infotainment display.

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Infotainment System 153
Availability of apps and connectivity varies
by vehicle, conditions, and location. Data
plan rates apply. Features are subject to
change. For more information, see
www.my.gmc.com/learn.
OnStar Services
If equipped, touch the OnStar Services icon
to display the OnStar Services and Account
pages. SeeOnStar Overview 0440 and
OnStar System 0162.
Camera
If equipped, touch the Camera icon to access
the camera application. See Assistance
Systems for Parking or Backing 0266.
Shortcut Tray
The shortcut tray is near the bottom of the
display. It shows up to four applications.
Infotainment Display Features
Infotainment display features show on the
display when available. When a feature is
unavailable, it may gray out. When a
feature is touched, it may highlight.
Haptic Feedback
If equipped, haptic feedback is a pulse that
occurs when an icon or option is touched on
the display or when controls on the center
stack are pressed.
Infotainment Gestures
Use the following finger gestures to control
the infotainment system.
Touch/Tap
Touch/tap is used to select an icon or
option, activate an application, or change
the location inside a map. Touch and Hold
Touch and hold can be used to start another
gesture, or to move or delete an application.
Drag
Drag is used to move applications on the
Home Page, or to pan the map. To drag the
item, it must be held and moved along the
display to the new location. This can be

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Infotainment System 157
seconds. The radio will also display
icons representing additional channels
(HD2, ...HD8), that may be available.
When the radio successfully tunes to a
HD station, the HD logo will display and
digital audio will play.
2. Touch the display arrows to tune to the previous or next HD Radio station.
There may be a delay before the station
starts playing.
The HD Radio station number is indicated
next to the HD logo.
HD Radio stations can be saved as favorites.
For a list of all stations, see
www.hdradio.com.
HD Radio Troubleshooting
Digital Audio Delay : Wait for the signal to
process. This can take several seconds.
Volume Change, Audio Skip, Echo, Digital
Audio Lost : Station signal strength may be
weak, the station is out of range, or the
station may be out of alignment. Verify
proper reception on another station.
If the HD Radio signal weakens while
listening to HD1, the radio will automatically
switch to the analog version of the radio
station. If the HD Radio signal loses reception while
listening to stations HD2 to HD8, the radio
mutes until the signal can be recovered or
until the station is changed.
HD Radio can be disabled if driving in a
weak signal area. Touch HD Radio On/Off to
toggle HD Radio reception on and off.
Radio Data System (RDS)
If equipped, RDS features are available for
use only on FM stations that broadcast RDS
information. With RDS, the radio can:
.Group stations by Category (i.e., Program
Type) such as Rock, Jazz, Classical, etc.
.Display messages from radio stations.
This system relies on receiving specific
information from these stations and only
works when the information is available.
It is possible that a radio station could
broadcast incorrect information that causes
the radio features to work improperly. If this
happens, contact the radio station.
When information is broadcast from a RDS
station, the station name or call letters
display on the audio screen. Radio text
supporting the currently playing broadcast
may also appear.
Satellite Radio
SiriusXM Radio Service
If equipped, vehicles with a valid SiriusXM
radio subscription can receive SiriusXM
programming.
SiriusXM radio has a wide variety of
programming and commercial-free music,
coast to coast, in digital-quality sound. In
the U.S., see www.siriusxm.com or call
1-888-601-6296. In Canada, see
www.siriusxm.ca or call 1-877-438-9677.
When SiriusXM is active, the channel name,
number, song title, and artist appear on the
display.
SiriusXM with 360L
SiriusXM with 360L interface has enhanced
in-vehicle listening experience for
subscribers. The experience now offers more
categories and system learned
recommendations toward discovering more
personalized content.
To use the full SiriusXM 360L program,
including streaming content and listening
recommendations, OnStar Connected Access
is required. Connected vehicle services vary

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158 Infotainment System
by model and require a complete working
electrical system, cell reception, and GPS
signal. An active connected plan is required.
Reference the SiriusXM user guide for use
and subscription information.
Radio Reception
Unplug electronic devices from the accessory
power outlets if there is interference or
static in the radio.
FM
FM signals only reach about 16 to 65 km (10
to 40 mi). Although the radio has a built-in
electronic circuit that automatically works to
reduce interference, some static can occur,
especially around tall buildings or hills,
causing the sound to fade in and out.
AM
The range for most AM stations is greater
than for FM, especially at night. The longer
range can cause station frequencies to
interfere with each other. Static can also
occur when things like storms and power
lines interfere with radio reception. When
this happens, try reducing the treble on the
radio.
SiriusXM Satellite Radio Service
If equipped, SiriusXM Satellite Radio Service
provides digital radio reception. Tall
buildings or hills can interfere with satellite
radio signals, causing the sound to fade in
and out. In addition, traveling or standing
under heavy foliage, bridges, garages,
or tunnels may cause loss of the SiriusXM
signal for a period of time. Some cellular
services may interfere with SXM reception
causing loss of signal.
Mobile Device Usage
Mobile device usage, such as making or
receiving calls, charging, or just having the
mobile device on may cause static
interference in the radio. Unplug the mobile
device or turn it off if this happens.
Fixed Mast Antenna
The fixed mast antenna will go through
most car washes as long as it is securely
attached. If the antenna becomes slightly
bent, straighten it out by hand. If it is badly
bent, replace it.
Occasionally check that the antenna is tight
at the base. If tightening is required, protect
the paint from damage.
Multi-Band Antenna
The roof antenna is for SiriusXM Satellite
Radio, OnStar, and GPS (Global Positioning
System), depending on the equipped
options. Keep clear of obstructions for clear
reception. If the vehicle has a sunroof, and it
is open, reception can also be affected.
Audio Players
Avoiding Untrusted Media Devices
When using media devices such as SD cards,
USB devices, and mobile devices, consider
the source. Untrusted media devices could
contain files that affect system operation or
performance. Avoid use if the content or
origin cannot be trusted.
USB Port
This vehicle is equipped with two USB ports
in the center console under the armrest and
another two in the center stack. These ports
are for data and charging.
There may also be two USB ports for
charging only at the rear of the center
console.

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162 Infotainment System
AUX Menu
Press MENU on the center stack to display
the AUX Input menu and the following may
display:
Tone Settings :Touch to adjust Bass,
Midrange, Treble, Balance, Fade, and EQ
(Equalizer). See AM-FM Radio0155.
Auto Volume (If Equipped) : This feature
adjusts the volume based on the vehicle
speed. See AM-FM Radio 0155.
Bose AudioPilot Noise Compensation
Technology (If Equipped) : This feature
adjusts the volume based on the noise in
the vehicle and speed. See “Bose AudioPilot”
in AM-FM Radio 0155.
Bluetooth Audio
Music may be played from a paired
Bluetooth device. See Bluetooth (Pairing and
Using a Phone) 0181 or
Bluetooth (Overview) 0180 for help pairing
a device.
Volume and song selection may be
controlled by using the infotainment
controls or the mobile device. If Bluetooth is
selected and no volume is present, check the
volume setting on the infotainment system. Music can be launched by touching
Bluetooth from the recent sources list on
the left of the display or by touching the
More option and then touching the
Bluetooth device.
To play music via Bluetooth:
1. Power on the device, and pair to connect the device.
2. Once paired, touch Audio from the Home Page, then touch Bluetooth from the
recent sources list on the left of the
display.
Bluetooth Sound Menu
See “Infotainment System Sound Menu”
under AM-FM Radio 0155.
Manage Bluetooth Devices
From the Home Page: 1. Touch Audio.
2. Touch More.
3. Touch Bluetooth.
4. Touch Devices to add or delete devices.
When touching Bluetooth, the radio may
not be able to launch the audio player on
the connected device to start playing. When
the vehicle is not moving, use the mobile
device to begin playback. All devices launch audio differently. When
selecting Bluetooth as a source, the radio
may show as paused on the display. Press
play on the device or touch
pon the
display to begin playback.
Browse functionality will be provided where
supported by the Bluetooth device. This
media content will not be part of the
MyMedia source mode.
Some smartphones support sending
Bluetooth music information to display on
the radio. When the radio receives this
information, it will check to see if any is
available and display it. For more
information about supported Bluetooth
features, see my.gmc.com/learn.
OnStar System
4G LTE
If equipped with 4G LTE, up to seven
devices, such as smartphones, tablets, and
laptops, can be connected to high-speed
Internet through the vehicle’s built-in Wi-Fi
hotspot.
Call 1-888-4ONSTAR (1-888-466-7827) to
connect to an OnStar Advisor for assistance.
See www.onstar.com for vehicle availability,

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Infotainment System 163
details, and system limitations. Service and
connectivity may vary by make, model,
year, carrier, availability, and conditions.
4G LTE service is available in select markets.
4G LTE performance is based on industry
averages and vehicle systems design. Some
services require a data plan.
The OnStar App
If equipped, the infotainment system has
OnStar controls in the embedded OnStar app
on the Home Page. Most OnStar functions
that can be performed with the buttons can
be done using the app. To open the app,
touch the OnStar icon on the Home Page.
App updates require a corresponding service
plan. Features vary by region and model.
Features are subject to change. For more
information, see my.gmc.com/learn or
press
Q.
Services
The Services tab displays the default view
for the app. Use this page to launch the
available OnStar services. Touch a service to
open its display. Touch Wi-Fi to launch the
connections manager. Turn-by-Turn and
Advisor Call are the other tiled options. Account
The Account tab displays a snapshot of the
account linked with the vehicle. If there is
no such account, this tab will show all
values as
——. The advisor call icon will be
active even if there is no active account.
Advisor Call
Selecting Advisor Call is the same as
pressing
Qor calling 1-888-4ONSTAR
(1-888-466-7827). The X option in the upper
right corner of the screen does not end the
call, but returns to the previous screen.
Turn-by-Turn Directions
With a connected plan, an OnStar Advisor
can download a destination to the vehicle or
its embedded navigation system,
if equipped. Select Turn-by-Turn Directions
from the Services tab of the OnStar app to
call an Advisor or select a recent or favorite
destination. Touch the navigation icons to
select home, address or place. A destination
transfer from OnStar will show the detail
view of the destination when it is
transferred from OnStar to the Navigation
application. See www.onstar.com for a
coverage map. Services vary by model. Map
coverage is available in the United States,
Puerto Rico, and Canada. Wi-Fi Hotspot
Touch to display the Settings page, which
shows the configurations for the vehicle
hotspot and allows them to be changed.
For more information, see www.onstar.com.
Navigation
Using the Navigation System
If equipped, launch the Nav application by
touching the Nav icon on the Home Page or
on the shortcut tray near the bottom of the
infotainment display.
When the Nav application is launched for
the first time, a product walkthrough is
available. Use of the feature requires the
Terms and Conditions and the Privacy
statement to be confirmed. If available and
signed into a profile, it is also suggested to
enable and confirm Predictive Navigation.
Predictive Navigation (If Equipped)
If Predictive Navigation is available and
confirmed, this feature learns preferences by
remembering where the vehicle has been.
It uses the locations and navigation history
to personalize routes and results.