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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/6/20
140 Lighting
for an additional 10 minutes. To keep the
lamps on for more than 10 minutes, the
ignition must be on or in ACC/ACCESSORY.
K:If equipped, turns on the task
lighting. See Task Lighting 0144.
IntelliBeam System
If equipped, this system turns the vehicle's
high-beam headlamps on and off according
to surrounding traffic conditions.
The system turns the high-beam headlamps
on when it is dark enough and there is no
other traffic present.
This light
bcomes on in the instrument
cluster when the IntelliBeam system is
enabled.
Turning On and Enabling IntelliBeam
To enable the IntelliBeam system, press
bon the turn signal lever when it is
dark outside and the exterior lamp control is
in AUTO or
2.
Driving with IntelliBeam
The system only activates the high beams
when driving over 40 km/h (25 mph).
The blue high-beam on light appears on the
instrument cluster when the high beams
are on.
There is a sensor near the top center of the
windshield that automatically controls the
system. Keep this area of the windshield
clear of debris to allow for best system
performance.
The high-beam headlamps remain on, under
the automatic control, until one of the
following situations occurs:
.The system detects an approaching
vehicle's headlamps.
.The system detects a preceding vehicle's
taillamps.
.The outside light is bright enough that
high-beam headlamps are not required.
.The vehicle's speed drops below 20 km/h
(12 mph).
.The IntelliBeam system is disabled by the
button on the turn signal lever. If this
happens, press
bon the turn signal
lever when the exterior lamp control is in
the AUTO or
2position to reactivate the
IntelliBeam system. The instrument
cluster light will come on to indicate the
IntelliBeam system is reactivated.
The high beams may not turn off
automatically if the system cannot detect
another vehicle's lamps because of any of
the following:
.The other vehicle's lamps are missing,
damaged, obstructed from view,
or otherwise undetected.
.The other vehicle's lamps are covered
with dirt, snow, and/or road spray.
.The other vehicle's lamps cannot be
detected due to dense exhaust, smoke,
fog, snow, road spray, mist, or other
airborne obstructions.
.The vehicle's windshield is dirty, cracked,
or obstructed by something that blocks
the view of the light sensor.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/6/20
146 Lighting
+ON/OFF :Press to turn the dome lamps
on manually. Press again to turn the dome
lamps off.
Reading Lamps
There are reading lamps on the overhead
console and over the rear seats. These lamps
come on when any door is opened.
To operate, the ignition must be on, or in
ACC/ACCESSORY, or using Retained Accessory
Power (RAP).
Front Reading Lamps
The front reading lamps are in the overhead
console. Press the lamp lenses to turn the front
reading lamps on or off.
Rear Reading Lamps
The rear reading lamps are over the rear
seats.
Press the lamp lens to turn the rear reading
lamps on or off.
Lighting Features
Entry Lighting
Some exterior lamps turn on briefly at
night, or in areas with limited lighting,
when
Kis pressed on the remote key. After
about 30 seconds the exterior lamps turn
off. When any door is opened or the remote
unlock is pressed, all interior lights turn on
and then interior lamps dim to off after
20 seconds. The entry lighting feature for exterior
lighting can be changed. See
“Vehicle
Locator Lights” underVehicle Personalization
0 131.
Exit Lighting
Some exterior lamps come on at night, or in
areas with limited lighting, when the driver
door is opened after the ignition is turned
off. The dome lamp comes on when any
door is opened or after the ignition is
turned off. The exterior lamps and dome
lamp remain on after the door is closed for
a set amount of time, then automatically
turn off.
The exterior lamps turn off immediately by
turning the exterior lamp control off.
The exit lighting for exterior lights can be
changed. See Vehicle Personalization 0131.
Battery Load Management
The vehicle has Electric Power Management
(EPM), which estimates the battery's
temperature and state of charge. It then
adjusts the voltage for best performance
and extended life of the battery.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Infotainment System 187
System
The menu may contain the following:
Time / Date
Use the following features to set the clock:
.Automatic Time and Date: Touch Off or
On to enable or disable automatic update
of the time and date. When this feature
is on, the time and date cannot be
manually set.
.Set Time: Touch to manually set the time
using the controls on the infotainment
display.
.Set Date: Touch to manually set the date
using the controls on the infotainment
display.
.Automatic Time Zone (If Equipped): Touch
Off or On to disable or enable automatic
update of the time zone based on vehicle
location. When this feature is on, the
time zone cannot be manually set.
.Select Time Zone: Touch to manually set
the time zone. Touch a time zone from
the list.
.Use 24-hour Format: Touch to specify the
clock format shown.
Touch Off or On to disable or enable.Language
This will set the display language used on
the infotainment display. It may also use
the selected language for voice recognition
and audio feedback. Touch Language and
touch the appropriate language.
Phones
Touch to connect to a different cell phone or
mobile device source, disconnect a cell
phone or media device, or delete a cell
phone or media device.
Wi-Fi Networks
This will show connected and available Wi-Fi
networks.
If a 4G LTE data package is not active on the
vehicle, the infotainment system can be
connected to an external protected Wi-Fi
network, such as a mobile device or home
hotspot, to utilize connected services.
Wi-Fi Hotspot
Touch and the following may display:
.Wi-Fi Services: This allows devices to use
the vehicle hotspot.
Touch the controls on the infotainment
display to disable or enable.
.Wi-Fi Name: Touch to change the vehicle
Wi-Fi name.
.Wi-Fi Password: Touch to change the
vehicle Wi-Fi password.
.Connected Devices: Touch to show
connected devices.
.Share Hotspot Data: Touch On to allow
devices to use the vehicle hotspot and its
data, or touch Off to allow devices to
only use the vehicle hotspot but not
its data.
Privacy
Touch and the following may display:
.Location Services: This setting enables or
disables sharing of vehicle location
outside the vehicle. Emergency services
will not be affected when Off is selected.
.Data Services: If equipped, this setting
determines if data sharing can be used by
features including Wi-Fi, Hotspot, and
applications. Touch Off to disable data
services. Emergency services and phone
calls, such as calls with OnStar Advisors or
others, will not be affected when Off is
selected.
.Voice Recognition Sharing: This setting
determines if voice commands can be
shared with a cloud-based voice

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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196 Infotainment System
performance standards. Apple is not
responsible for the operation of this device
or its compliance with safety and regulatory
standards. Please note that the use of this
accessory with iPod or iPhone may affect
wireless performance. iPhone, iPod, iPod
classic, iPod nano, iPod shuffle, and iPod
touch are trademarks of Apple Inc.,
registered in the U.S. and other countries.
If you decide to continue service after your
trial, your selected subscription plan will
automatically renew thereafter. You will be
charged at then-current rates. Fees and taxes
apply. Please see the SiriusXM Customer
Agreement at siriusxm.com for complete
terms and how to cancel, which includes
calling SiriusXM at 1-866-635-2349. All fees
and programming are subject to change.
Fees and Taxes: Subscription fee, taxes, one
time activation fee, and other fees may
apply. Subscription fee is consumer only. All
fees and programming subject to change.
Subscriptions subject to CustomerAgreement available at www.siriusxm.com.
SiriusXM service is only available in the
48 contiguous United States and Canada.
In Canada: Some deterioration of service
may occur in extreme northern latitudes.
This is beyond the control of SiriusXM
Satellite Radio.
Explicit Language Notice: Channels with
frequent explicit language are indicated with
an
“XL” preceding the channel name.
Channel blocking is available for SiriusXM
Satellite Radio receivers by notifying
SiriusXM:
.USA Customers —See www.siriusxm.com
or call 1-888-601–6296.
.Canada Customers —See
www.siriusxm.ca or call 1-877-438-9677.
It is prohibited to copy, decompile,
disassemble, reverse engineer, hack,
manipulate, or otherwise make available any
technology or software incorporated in
receivers compatible with the SiriusXM
Satellite Radio System or that support the
SiriusXM website, the Online Service or any
of its content. Furthermore, the AMBER voice
compression software included in this
product is protected by intellectual property rights including patent rights, copyrights,
and trade secrets of Digital Voice
Systems, Inc.
General Requirements:
1. A License Agreement from SiriusXM is required for any product that
incorporates SiriusXM Technology and/or
for use of any of the SiriusXM marks to
be manufactured, distributed,
or marketed in the SiriusXM
Service Area.
2. For products to be distributed, marketed, and/or sold in Canada, a separate
agreement is required with Canadian
Satellite Radio Inc. (operating as SiriusXM
Canada).
TouchSense Technology and TouchSense
System 1000 Series Licensed from
Immersion Corporation. TouchSense System
1000 protected under one or more of the

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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204 Climate Controls
Climate Controls
Climate Control Systems
Climate Control Systems . . . . . . . . . . . . . . 204
Dual Automatic Climate ControlSystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Maintenance
Passenger Compartment Air Filter . . . . . 209
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Climate Control Systems
The heating, cooling, and ventilation in the vehicle can be controlled with this system.
1. Fan Control
2. MAX Defrost
3. Air Delivery Mode Controls
4. A/C (Air Conditioning)
5. TEMP (Temperature Control)
6. Recirculation
7. Rear Window Defogger (If Equipped) or Heated Mirrors (If Equipped)9:Turn clockwise or counterclockwise to
increase or decrease the fan speed. Turn the
knob all the way counterclockwise to turn
the fan off.
TEMP : Turn clockwise or counterclockwise
to increase or decrease the temperature
inside the vehicle.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Climate Controls 207
The fan, air delivery mode, air conditioning,
driver and passenger temperatures, and Sync
settings can be controlled by touching
CLIMATE on the infotainment Home Page or
the climate button in the climate control
display application tray. A selection can then
be made on the front climate control page
displayed.
Climate Control Status Display
The climate control status display appears
briefly when the center stack climate
controls are adjusted.Automatic Operation
The system automatically controls the fan
speed, air delivery, air conditioning, and
recirculation in order to heat or cool the
vehicle to the desired temperature.
When AUTO is lit, all four functions operate
automatically. Each function can also be
manually set and the selected setting is
displayed. Functions not manually set will
continue to be automatically controlled,
even if the AUTO indicator is not lit.
For automatic operation:
1. Press AUTO.
2. Set the temperature. Allow the system time to stabilize. Adjust the temperature
as needed for best comfort.
To improve fuel efficiency and to cool the
vehicle faster, recirculation may be
automatically selected in warm weather.
The recirculation light will not come on
when automatically controlled. See@
under “Manual Operation” for more details.
Manual Operation
9:Turn clockwise or counterclockwise to
increase or decrease the fan speed. Press the
knob to turn the fan off. When off is selected, a small amount of air may still
come out of the outlets depending on
vehicle speed. If any buttons are pressed or
knobs are turned, the climate control system
will turn on and operate at the current
setting.
Press AUTO to return to automatic
operation.
Driver and Passenger Temperature Control :
The temperature can be adjusted separately
for the driver and passenger.
Turn the knob clockwise or counterclockwise
to increase or decrease the driver or
passenger temperature setting. The driver
side or passenger side temperature display
shows the temperature setting increasing or
decreasing.
SYNC :
Press to link the passenger
temperature setting to the driver setting.
The SYNC indicator light will turn on. When
the passenger setting is adjusted, the SYNC
indicator light will turn off.
Air Delivery Mode Control : Press
z,Y,
or
[to change the direction of the
airflow. Any combination of the three
controls can be selected. An indicator light
comes on in the selected mode button.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Climate Controls 209
The solar sensor, on top of the instrument
panel near the windshield, monitors the
solar heat.
The climate control system uses the sensor
information to adjust the temperature, fan
speed, recirculation, and air delivery mode
for best comfort.
Do not cover the sensor; otherwise the
automatic climate control system may not
work properly.
Air Vents
Use the sliding knobs on the center and side
air vents to change the direction of the
airflow.
Air vents blow warm air on the side
windows in cold weather. If Floor, Defog,
or Defrost modes are selected, a small
amount of air will come from the vents
close to the window.
To close the front a/c vents, move the
sliding knobs to the full down position.
To close the rear a/c vents, move the sliding
knobs to the full inboard position.Operation Tips
.Clear away any ice, snow, or leaves from
air inlets at the base of the windshield
that could block the flow of air into the
vehicle.
.Clear snow off the hood to improve
visibility and help decrease moisture
drawn into the vehicle.
.Keep the path under the front seats clear
of objects to help circulate the air inside
of the vehicle more effectively.
.Use of non-GM approved hood deflectors
can adversely affect the performance of
the system. Check with your dealer
before adding equipment to the outside
of the vehicle.
.Do not attach any devices to the air vent
slats. This will restrict airflow and may
cause damage to the air vents.
Maintenance
Passenger Compartment Air Filter
The filter reduces the dust, pollen, and other
airborne irritants from outside air that is
pulled into the vehicle.
The filter should be replaced as part of
routine scheduled maintenance. See
Maintenance Schedule
0409. To find out
what type of filter to use, see Maintenance
Replacement Parts 0419.
1. Open the lower glove box door
completely.

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Driving and Operating 211
Driving and Operating
Driving Information
Driving for Better Fuel Economy . . . . . . . 212
Distracted Driving . . . . . . . . . . . . . . . . . . . . . . 212
Defensive Driving . . . . . . . . . . . . . . . . . . . . . . 213
Impaired Driving . . . . . . . . . . . . . . . . . . . . . . . 213
Control of a Vehicle . . . . . . . . . . . . . . . . . . . . 213
Braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Off-Road Recovery . . . . . . . . . . . . . . . . . . . . . 214
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . . 215
Off-Road Driving . . . . . . . . . . . . . . . . . . . . . . . 215
Driving on Wet Roads . . . . . . . . . . . . . . . . . 219
Hill and Mountain Roads . . . . . . . . . . . . . . 219
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . 220
If the Vehicle Is Stuck . . . . . . . . . . . . . . . . . . 221
Vehicle Load Limits . . . . . . . . . . . . . . . . . . . . 222
Truck-Camper Loading Information . . . . 226
Starting and Operating
New Vehicle Break-In . . . . . . . . . . . . . . . . . . 228
Ignition Positions (Key Access) . . . . . . . . 229
Ignition Positions (Keyless Access) . . . . . 230
Starting the Engine . . . . . . . . . . . . . . . . . . . . 232
Stop/Start System . . . . . . . . . . . . . . . . . . . . . 233
Engine Heater . . . . . . . . . . . . . . . . . . . . . . . . . 234
Retained Accessory Power (RAP) . . . . . . . 236
Shifting Into Park . . . . . . . . . . . . . . . . . . . . . 236
Shifting out of Park . . . . . . . . . . . . . . . . . . . 237Parking over Things That Burn . . . . . . . . . 237
Active Fuel Management . . . . . . . . . . . . . . 237
Extended Parking . . . . . . . . . . . . . . . . . . . . . . 238
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . . . . . . . . . . . 238
Running the Vehicle While Parked . . . . . 238
Automatic Transmission
Automatic Transmission . . . . . . . . . . . . . . . 239
Manual Mode . . . . . . . . . . . . . . . . . . . . . . . . . 241
Tow/Haul Mode . . . . . . . . . . . . . . . . . . . . . . . 242
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 242
Brakes
Electric Brake Boost . . . . . . . . . . . . . . . . . . . 246
Antilock Brake System (ABS) . . . . . . . . . . 246
Electric Parking Brake . . . . . . . . . . . . . . . . . . 247
Brake Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . 248
Ride Control Systems
Traction Control/Electronic Stability
Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Hill Descent Control (HDC) . . . . . . . . . . . . 250
Driver Mode Control . . . . . . . . . . . . . . . . . . . 251
Limited-Slip Differential . . . . . . . . . . . . . . . . 254
Locking Rear Axle . . . . . . . . . . . . . . . . . . . . . 254
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . 254
Adaptive Cruise Control (Camera) . . . . . . 256
Driver Assistance Systems
Driver Assistance Systems . . . . . . . . . . . . . 265
Assistance Systems for Parking or Backing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266
Assistance Systems for Driving . . . . . . . . 274
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
Automatic Emergency Braking (AEB) . . . 277
Front Pedestrian Braking (FPB) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Side Blind Zone Alert (SBZA) . . . . . . . . . . 280
Lane Change Alert (LCA) . . . . . . . . . . . . . . . 280
Lane Keep Assist (LKA) . . . . . . . . . . . . . . . . . 281
Fuel
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Recommended Fuel (Except 6.2L V8 Engine) . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Recommended Fuel (6.2L V8 Engine) . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . 284
Fuels in Foreign Countries . . . . . . . . . . . . . 284
Fuel Additives . . . . . . . . . . . . . . . . . . . . . . . . . 284
E85 or FlexFuel . . . . . . . . . . . . . . . . . . . . . . . . 284
Filling the Tank (Pickup Model) . . . . . . . . 285
Filling the Tank (Chassis Cab Model) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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214 Driving and Operating
Steering
Caution
To avoid damage to the steering system,
do not drive over curbs, parking barriers,
or similar objects at speeds greater than
3 km/h (1 mph). Use care when driving
over other objects such as lane dividers
and speed bumps. Damage caused by
misuse of the vehicle is not covered by
the vehicle warranty.
Electric Power Steering
The vehicle has electric power steering.
It does not have power steering fluid.
Regular maintenance is not required.If power steering assist is lost due to a
system malfunction, the vehicle can be
steered, but may require increased effort.
If the steering assist is used for an extended
period of time while the vehicle is not
moving, power assist may be reduced.
If the steering wheel is turned until it
reaches the end of its travel and is held
against that position for an extended period
of time, power steering assist may be
reduced.
Normal use of the power steering assist
should return when the system cools down.
See your dealer if there is a problem.
Curve Tips
.Take curves at a reasonable speed.
.Reduce speed before entering a curve.
.Maintain a reasonable steady speed
through the curve.
.Wait until the vehicle is out of the curve
before accelerating gently into the
straightaway.
Steering in Emergencies
.There are some situations when steering
around a problem may be more effective
than braking.
.Holding both sides of the steering wheel
allows you to turn 180 degrees without
removing a hand.
.The Antilock Brake System (ABS) allows
steering while braking.
Off-Road Recovery
The vehicle's right wheels can drop off the
edge of a road onto the shoulder while
driving. Follow these tips:
1. Ease off the accelerator and then, if there is nothing in the way, steer the
vehicle so that it straddles the edge of
the pavement.