warning GMC SIERRA 2021 Repair Manual

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Instruments and Controls 121
serviced by your dealer. If the system is
working normally, the indicator light then
turns off. This light comes on when the
Electronic Stability Control (ESC) system is
turned off. If ESC is off, the Traction Control
System (TCS) is also off. To turn ESC off and
on, seeTraction Control/Electronic Stability
Control 0248.
If ESC and TCS are off, the systems do not
assist in controlling the vehicle. Adjust
driving accordingly.
Engine Coolant Temperature
Warning Light
This light comes on briefly while starting
the vehicle.
If it does not, have the vehicle serviced by
your dealer. If the system is working
normally the indicator light goes off.
Caution
The engine coolant temperature warning
light indicates that the vehicle has
overheated. Driving with this light on can
damage the engine and it may not be
covered by the vehicle warranty. See
Engine Overheating 0338.
The engine coolant temperature warning
light comes on when the engine has
overheated.
If this happens, pull over and turn off the
engine as soon as possible. See Engine
Overheating 0338.
Driver Mode Control Light
This light comes on when Sport Mode is
selected.
This light comes on when Snow/Ice Mode is
selected.
This light comes on when Terrain Mode is
selected.
This light comes on when Off-Road Mode is
selected.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
122 Instruments and Controls
Tire Pressure Light
For vehicles with the Tire Pressure Monitor
System (TPMS), this light comes on briefly
when the engine is started. It provides
information about tire pressures and
the TPMS.
When the Light Is On Steady
This indicates that one or more of the tires
are significantly underinflated.
A Driver Information Center (DIC) tire
pressure message may also display. Stop as
soon as possible, and inflate the tires to the
pressure value shown on the Tire and
Loading Information label. SeeTire Pressure
0 367.
When the Light Flashes First and Then Is On
Steady
If the light flashes for about a minute and
then stays on, there may be a problem with
the TPMS. If the problem is not corrected, the light will come on at every ignition
cycle. See
Tire Pressure Monitor Operation
0 369.
Engine Oil Pressure Light (Uplevel
Cluster)
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.
This light should come on briefly as the
engine is started. If it does not come on,
have the vehicle serviced by your dealer. If the light comes on and stays on, it means
that oil is not flowing through the engine
properly. The vehicle could be low on oil
and might have some other system
problem. See your dealer.
Low Fuel Warning Light
This light is near the fuel gauge and comes
on briefly when the ignition is turned on as
a check to show it is working.
It also comes on when the fuel tank is low
on fuel. The light turns off when fuel is
added. If it does not, have the vehicle
serviced.
Security Light

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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128 Instruments and Controls
Head-Up Display (HUD)
{Warning
If the HUD image is too bright or too
high in your field of view, it may take
you more time to see things you need to
see when it is dark outside. Be sure to
keep the HUD image dim and placed low
in your field of view.
If equipped with HUD, some information
about the operation of the vehicle is
projected onto the windshield. The image is
projected through the HUD lens on top of
the instrument panel. The information
appears as an image focused out toward the
front of the vehicle.
Caution
If you try to use the HUD image as a
parking aid, you may misjudge the
distance and damage your vehicle. Do not
use the HUD image as a parking aid.
The HUD information can be displayed in
various languages. The speedometer reading
and other numerical values can be displayed
in either English or metric units. The language selection is changed through
the radio, and the units of measurement is
changed through the instrument cluster. See
Settings
0186 and “Options” under
Instrument Cluster 0106.
HUD Display on the Windshield
Depending on how the vehicle is equipped,
the HUD may display some of the following
vehicle information and vehicle messages or
alerts:
.Speed
.Audio
.Phone
.Navigation
.Driver Assistance Features
.Vehicle Messages Some vehicle messages or alerts displayed in
the HUD may be cleared by using the
steering wheel controls.
The HUD control is to the left of the
steering wheel.
To adjust the HUD image:
1. Adjust the driver seat.
2. Start the engine.
3. Use the following settings to adjust the HUD.
$:Press or pull to center the HUD image.
The HUD image can only be adjusted up and
down, not side to side.
!: Press to select the display view. Each
press will change the display view.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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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

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Lighting 139
Lighting
Exterior Lighting
Exterior Lamp Controls . . . . . . . . . . . . . . . . 139
Exterior Lamps Off Reminder . . . . . . . . . . . 141
Headlamp High/Low-Beam Changer . . . . 141
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Daytime Running Lamps (DRL) . . . . . . . . . 141
Automatic Headlamp System . . . . . . . . . . 142
Hazard Warning Flashers . . . . . . . . . . . . . . 142
Turn and Lane-Change Signals . . . . . . . . . 143
Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Task Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Auxiliary Roof-Mounted Lamp . . . . . . . . . 144
Exterior Cargo Lamps . . . . . . . . . . . . . . . . . . 144
Interior Lighting
Instrument Panel IlluminationControl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Reading Lamps . . . . . . . . . . . . . . . . . . . . . . . . 146
Lighting Features
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . . . . 146
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Battery Load Management . . . . . . . . . . . . 146
Battery Power Protection . . . . . . . . . . . . . . 147
Exterior Lighting Battery Saver . . . . . . . . 147
Exterior Lighting
Exterior Lamp Controls
The exterior lamp control is on the
instrument panel to the left of the steering
wheel.
O: Turns off the automatic headlamps and
Daytime Running Lamps (DRL). Turn the
headlamp control to
Oagain to turn the
automatic headlamps or DRL back on.
For vehicles first sold in Canada, off will only
work when the vehicle is in P (Park). AUTO :
Automatically turns on the
headlamps, parking lamps, taillamps,
instrument panel lights, roof marker lamps
(if equipped), front/rear sidemarker lamps,
and license plate lamps.
;: Turns on the parking lamps including
all lamps, except the headlamps and fog
lamps, if equipped.
For some trim levels and series of trucks
first sold in Canada, the headlamps may
turn on with the parking lamps.
2: Turns on the headlamps together with
the parking lamps, taillamps, instrument
panel lights, roof marker lamps (if
equipped), front/rear sidemarker lamps, and
license plate lamps.
When the headlamps are turned on while
the vehicle is on, the headlamps turn off
automatically 10 minutes after the ignition
is turned off. When the headlamps are
turned on while the vehicle is off, the
headlamps will stay on for 10 minutes
before turning off to prevent the battery
from being drained. Turn the headlamp
control off and then back to the headlamp
on position to make the headlamps stay on

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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142 Lighting
Automatic Headlamp System
When the exterior lamp control is set to
AUTO and it is dark enough outside, the
headlamps come on automatically.
There is a light sensor on top of the
instrument panel. Do not cover the sensor,
otherwise the headlamps will come on when
they are not needed.
The system may also turn on the headlamps
when driving through a parking garage or
tunnel.
If the vehicle is started in a dark garage, the
automatic headlamp system comes on
immediately. If it is light outside when the
vehicle leaves the garage, there is a slightdelay before the automatic headlamp
system changes to the Daytime Running
Lamps (DRL). During that delay, the
instrument cluster may not be as bright as
usual. Make sure the instrument panel
illumination control is in the full bright
position. See
Instrument Panel Illumination
Control 0145.
When it is bright enough outside, the
headlamps will turn off or may change
to DRL.
The automatic headlamp system turns off
when the exterior lamp control is turned to
Oor the ignition is off.
Lights On with Wipers
If the windshield wipers are activated in
daylight with the engine on, and the
exterior lamp control is in AUTO, the
headlamps, parking lamps, and other
exterior lamps come on. The transition time
for the lamps coming on varies based on
wiper speed. When the wipers are not
operating, these lamps turn off. Move the
exterior lamp control to
Oor;to disable
this feature.
Hazard Warning Flashers
|: Press this button to make the front
and rear turn signal lamps flash on and off.
Press again to turn the flashers off.
When the hazard warning flashers are on,
the vehicle's turn signals will not work.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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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.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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194 Infotainment System
Manage Settings
Audio Volume Limit :Allows the audio
volume limit to be turned on or off. Touch
Set Audio Volume Limit to choose the
maximum allowable audio volume level.
Set Audio Volume Limit : Allows a
maximum radio volume to be set. Use the
arrows to choose the maximum allowable
level for the audio volume.
Teen Driver Speed Limiter : Limits the
maximum speed of the vehicle. When the
speed limiter is turned on and the vehicle is
started with a Teen Driver key, the DIC
displays a message that the top speed is
limited.
On certain vehicles, when the Speed Limiter
is turned ON, the vehicle’s maximum
acceleration will be limited. The DIC will
display a message that the acceleration is
limited.
Teen Driver Speed Warning : Allows the
speed warning to be turned on or off. Touch
Set Teen Driver Speed Warning to set the
warning speed. Set Teen Driver Speed Warning :
Displays a
warning in the DIC when exceeding a
selectable speed. Choose the desired speed
warning level. The speed warning does not
limit the speed of the vehicle.
SiriusXM Explicit Content Filter (if
equipped) : Allows the SiriusXM Explicit
Content Filter to be turned ON or OFF.
When ON, the teen driver will not be able
to listen to SiriusXM stations that contain
explicit content, and the Explicit Content
Filter selection in the Audio Settings will be
unavailable for change.
When Teen Driver is Active:
.If equipped with Buckle to Drive, shifting
out of P (Park) will be prevented if the
driver seat belt, and in some vehicles the
front passenger seat belt, is not buckled.
.The radio will mute when the driver seat
belt, and in some vehicles the front
passenger seat belt, is not buckled. The
audio from any device paired to the
vehicle will also be muted.
.An object placed on the front passenger
seat, such as a briefcase, handbag,
grocery bag, laptop, or other electronic
device, could cause the passenger sensing
system to falsely sense an unbuckled
front passenger and mute the radio. If this happens, remove the object from
the seat. See
Passenger Sensing System
0 66.
.Some safety systems, such as Forward
Collision Alert, if equipped, cannot be
turned off.
.The gap setting for the Forward Collision
Alert and Adaptive Cruise Control,
if equipped, cannot be changed.
.When trying to change a safety feature
that is not configurable in Teen Driver,
the DIC displays a message indicating
that Teen Driver is active and the action
is not available.
.Super Cruise, if equipped, is not available.
.Enhanced Low Fuel Warning (if equipped)
–When the vehicle is low on fuel, the
low fuel light on the instrument cluster
flashes and the DIC low fuel warning
cannot be dismissed.
.Do not tow a trailer.
Report Card
The vehicle owner must secure the driver’s
consent to record certain vehicle data when
the vehicle is driven with a registered Teen
Driver key. There is one Report Card per

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Infotainment System 195
vehicle. Data is only recorded when a
registered Teen Driver key is used to
operate the vehicle.
The Report Card data is collected from the
time Teen Driver is activated or the last
time the Report Card was reset. The
following items may be recorded:
.Distance Driven–the total distance
driven.
.Maximum Speed –the maximum vehicle
speed detected.
.Overspeed Warnings –the number of
times the speed warning setting was
exceeded.
.Wide Open Throttle –the number of
times the accelerator pedal was pressed
nearly all the way down.
.Forward Collision Alerts –the number of
times the driver was notified when
approaching a vehicle ahead too quickly
and at potential risk for a crash.
.Forward Automatic Braking, also called
Automatic Emergency Braking (if
equipped) –the number of times the
vehicle detected that a forward collision
was imminent and applied the brakes.
.Reverse Automatic Braking (if equipped) –
the number of times the vehicle detected
that a rearward collision was imminent
and applied the brakes.
.Traction Control –the number of times
the Traction Control System activated to
reduce wheel spin or loss of traction.
.Stability Control –the number of events
which required the use of electronic
stability control.
.Antilock Braking System Active –The
number of Antilock Brake System
activations.
.Tailgating Alerts –the number of times
the driver was alerted for following a
vehicle ahead too closely.
Report Card Data
Cumulative Data is saved for all trips until
the Report Card is reset or until the
maximum count is exceeded. If the
maximum count is exceeded for a Report
Card line item, that item will no longer be
updated in the Report Card until it is reset.
Each item will report a maximum of
1,000 counts. The distance driven will report
a maximum of 64 374 km (40,000 mi). To delete Report Card data, do one of the
following:
.From the Report Card display, touch
Reset.
.Touch Clear All Teen Keys and PIN from
the Teen Driver menu. This will also
unregister any Teen Driver keys and
delete the PIN.
Forgotten PIN
See your dealer to reset the PIN.
Trademarks and License
Agreements
FCC Information
See Radio Frequency Statement 0436.
"Made for iPod," and "Made for iPhone,"
mean that an electronic accessory has been
designed to connect specifically to iPod or
iPhone, respectively, and has been certified
by the developer to meet Apple

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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200 Infotainment System
guidance, fleet management or similar
applications; or (b) with, or in
communication with, including without
limitation, cellular phones, palmtop and
handheld computers, pagers, and personal
digital assistants or PDAs.
Warning
This Data may contain inaccurate or
incomplete information due to the passage
of time, changing circumstances, sources
used, and the nature of collecting
comprehensive geographic data, any of
which may lead to incorrect results.
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