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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Driving and Operating 257
{Warning
ACC will not detect or brake for children,
pedestrians, animals, or other objects.
Do not use ACC when:
.On winding and hilly roads or when
the camera sensor is blocked by snow,
ice, or dirt. The system may not
detect a vehicle ahead. Keep the
windshield and headlamps clean.
.When visibility is poor due to rain,
snow, fog, dirt, insect residue, or dust;
when other foreign objects obscure
the camera’s view; or when the
vehicle in front or oncoming traffic
causes additional environmental
obstructions, such as road spray. ACC
performance is limited under these
conditions.
.On slippery roads where fast changes
in tire traction can cause excessive
wheel slip
.With extremely heavy cargo loaded in
the cargo area or rear seat
.When towing a trailer
J:Press to turn the system on or off. The
indicator turns white on the instrument
cluster when ACC is turned on.
RES+ : Press briefly to resume the previous
set speed or to increase vehicle speed if ACC
is already activated. To increase speed by
about 1 km/h (1 mph), press RES+ briefly. To
increase speed to the next 5 km/h (5 mph)
mark on the speedometer, hold RES+.
SET– :Press briefly to set the speed and
activate ACC or to decrease vehicle speed if
ACC is already activated. To decrease speed
by about 1 km/h (1 mph), press SET– briefly.
To decrease speed to the next 5 km/h
(5 mph) mark on the speedometer,
hold SET–.
*: Press to disengage ACC without erasing
the selected set speed.
[: Press to select a following gap setting
for ACC of Far, Medium, or Near.
The speedometer reading can be displayed
in either English or metric units. See
Instrument Cluster 0106. The increment
value used depends on the units displayed.
Switching Between ACC and Regular Cruise
Control
To switch between ACC and regular cruise
control, press and hold
*. A Driver
Information Display (DIC) message displays.
See Vehicle Messages 0130.
ACC IndicatorRegular Cruise Control
Indicator
When ACC is engaged, a green
oindicator
will be lit on the instrument cluster and the
following gap will be displayed. When the

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Driving and Operating 263
When following a vehicle and entering a
curve, ACC may not detect the vehicle ahead
and accelerate to the set speed. When this
happens, the vehicle ahead indicator will not
appear.
ACC may detect a vehicle that is not in your
lane and apply the brakes.
ACC may occasionally provide an alert and/
or braking that is considered unnecessary.
It could respond to vehicles in different
lanes or stationary objects when entering or
exiting a curve. This is normal operation.
The vehicle does not need service.Other Vehicle Lane Changes
ACC will not detect a vehicle ahead until it
is completely in the lane. The brakes may
need to be manually applied.
Objects Not Directly in Front of Your Vehicle
The detection of objects in front of the
vehicle may not be possible if:
.The vehicle or object ahead is not within
your lane.
.The vehicle ahead is shifted, not centered,
or is shifted to one side of the lane.
Driving in Narrow Lanes
Vehicles in adjacent traffic lanes or roadside
objects may be incorrectly detected when
located along the roadway. Do Not Use ACC on Hills and When Towing a
Trailer
Do not use ACC when driving on steep hills
or when towing a trailer. ACC will not detect
a vehicle in the lane while driving on steep
hills. If the brakes are applied, ACC
disengages.
Disengaging ACC
There are three ways to disengage ACC:
.Step lightly on the brake pedal.
.Press*.
.PressJ.
Erasing Speed Memory
The ACC set speed is erased from memory if
Jis pressed or if the ignition is turned off.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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270 Driving and Operating
12 km/h (8 mph), touch CAMERA on
the infotainment display and touch
the Bed View icon. The view will close
after 8 seconds and can be closed
early by touching X.
10. Transparent Trailer View
Provides a view that allows the driver
to virtually“see through” the trailer.
The feature is available when a
compatible trailer is connected and a
profile is configured and selected via
the Trailering App. See Trailering App
0 307. The feature requires user
installation of an accessory trailer
camera on the rear exterior surface of
the trailer per the accessory trailer
camera installation instructions (see
your dealer for accessory trailer
camera(s) and information). To select,
touch Transparent Trailer View on the
infotainment display when a camera
view is active. To access this view
when in a forward gear above
12 km/h (8 mph), touch CAMERA on
the infotainment display and touch
the Transparent Trailer View icon.
Touch X to exit.
When the system is calibrated and the
trailer position is known, one of three
views will be shown; Transparent Trailer View, Left Transparent Trailer
View or Right Transparent Trailer
View. The Transparent Trailer View is
shown when the position of the trailer
is relatively straight behind the
vehicle. The Left or Right Transparent
Trailer View is shown when the
position of the trailer is too far to the
left or right. When the system is not
calibrated or trailer position is not
known the Transparent Trailer
Picture-in-Picture View will be shown.
11. Rear Trailer View/Rear Side View with
Available Articulation Functionality/
Picture-in-Picture Side View
.Rear Trailer View provides a view
of the area behind the trailer. the
feature is available when a trailer
is connected. The feature requires
user installation of an accessory
trailer camera on the rear exterior
surface of the trailer per the
accessory trailer camera
installation instructions (see your
dealer for accessory trailer
camera(s) and information). To
select, touch Rear Trailer View/Rear
Side View with Available
Articulation Functionality/
Picture-in-Pictue Side View on the infotainment display when a
camera view is active. Each touch
will toggle through the Rear Trailer
View, Trailer Tow Mirror View and
Combo View. To access this view
when in a forward gear above
12 km/h (8 mph), touch CAMERA
on the infotainment display and
touch the Interior Rear Trailer
View/Rear Side View with Available
Articulation Functionality/
Picture-in-Picture Side View icon.
Touch X to exit.
.Rear Side View with Available
Articulation Functionality provides
a rearward split view of the left
and right sides of the vehicle and
trailer. When in a forward gear the
view well automatically pan to
show more of the left or right side
based on the position of the
trailer. The feature is available
when a trailer is connected. To
select, touch Rear trailer View/Rear
Side View with Available
Articulation Functionality/
Picture-in-Picture Side View on the
infotainment display when a
camera view is active. Each touch
will toggle through the Rear Trailer

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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View, trailer tow Mirror view and
Combo View. To access this view
when in a forward gear above
12 km/h (8 mph), Touch CAMERA
on the infotainment display and
touch the Rear Trailer View/Rear
Side View with Available
Articulation Functionality/
Picture-in-Picture Side icon. Touch X
to exit.
.Provides a rearward split view of
the left and right sides of the
vehicle and trailer with an overlay
view of the area behind the trailer.
The feature is available when a
trailer is connected. the feature
requires user installation of an
accessory trailer camera on the
rear exterior surface of the trailer
per the accessory trailer camera
installation instructions (see your
dealer for accessory trailer
camera(s) and information). To
select, touch Rear Trailer View/Rear
Side View with Available
Articulation Functionality/
Picture-in-Picture Side view on the
infotainment display when a
camera view is active. Each press
of the button will toggle throughthe Rear Trailer View, Trailer Tow
mirror View and Combo View. To
access this view when in a forward
gear above 12 km/h (8 mph), touch
CAMERA on the infotainment
display and touch the Rear Trailer
View/Rear Side View with Available
Articulation Functionality/
Picture-in-Picture Side View icon.
Touch X to exit.
HD Surround Vision with Trailer Camera
Provisions
If equipped, this feature provides additional
views to aid in trailering/towing. The
system shows multiple views in the
infotainment display using five cameras
mounted around the vehicle and up to two
additional accessory cameras that can be
mounted on or in a trailer. The front camera
is in the grille under the front emblem, the
side cameras are on the bottom of the
outside mirrors, the rear camera is in the
tailgate handle and the bed camera is
mounted on the rear of the cab.
Additionally, up to two accessory cameras
can be mounted to the rear and/or interior
of the trailer. See your dealer for accessory
trailer cameras. To access, touch CAMERA on
the infotainment display or shift to R (Reverse). To return to the previous screen
when not in reverse, touch the Home or
Back buttons on the infotainment display.
Certain trailer views require a compatible
trailer profile be configured and selected.
A compatible trailer is a box type trailer
(cargo, camper, etc.) with a conventional
hitch.
Available camera views:.Front/Rear Standard View
.Front/Rear Top-Down View
.Rear Bowl View
.Front/Rear Side View
.Hitch View
.Bed View
.Rear trailer View
.Rear Side view with a available
articulation functionality
.Picture-in-Picture Side View
.Interior Trailer View
.Transparent trailer View
.Surround View
.Guidance Lines
.Hitch Guidance

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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272 Driving and Operating
Surround Vision (360 Degrees)
If equipped, the Surround Vision system can
display various views surrounding the
vehicle in the infotainment display using
four cameras mounted around the vehicle.
The front camera is in the grille under the
front emblem, the side cameras are on the
bottom of the outside mirrors, and the rear
camera is in the tailgate handle.
The Surround Vision system can be accessed
by selecting CAMERA in the infotainment
display or when the vehicle is shifted into
R (Reverse). To return to the previous screen
sooner, when not in R (Reverse), press the
Home or Back button on the infotainment
system, shift into P (Park), or, while in D
(Drive), reach a vehicle speed of
approximately 12 km/h (8 mph).
Available camera views:
.Front/Rear Standard View
.Front/Rear Top-Down View
.Rear Bowl View
.Front/Rear Side View
.Hitch View
.Surround View
.Guidance Lines
.Hitch GuidanceSurround Vision
If equipped, this feature provides, additional
views to aid in trailering/towing. The Front
Vision Camera and Surround Vision cameras
are not supported. The system can show
various views in the infotainment display
using cameras mounted in and around the
vehicle and trailer. The rear camera is in the
tailgate handle and the cargo bed camera is
mounted on the rear of the cab. Up to two
accessory cameras can be mounted to the
rear and/or interior of the trailer. See your
dealer for these accessory cameras.
The system can be accessed by selecting
CAMERA in the infotainment display or
when the vehicle is shifted into R (Reverse).
To return to the previous screen sooner,
when not in R (Reverse), press the Home or
Back button on the infotainment system or
shift into P (Park).
Available camera views:
.Rear Standard View
.Hitch View
.Bed View
.Rear Trailer View
.Interior Trailer View
.Guidance Lines
.Hitch GuidanceTroubleshooting
The Transparent Trailer calibration may take
longer than expected or not calibrate if:
.The vehicle is driven too fast during
calibration. Speed should be maintained
below 50 km/h (31 mph).
.The vehicle is not driven straight during
calibration. Steering should be maintained
as straight as possible, excessive steering
during calibration may extend
calibration time.
.The calibration is attempted in low light.
Calibration should be attempted when
there is enough light.
.The calibration is attempted during
adverse weather conditions. Calibration
during conditions such as snow or heavy
rain should be avoided.
.The road surface is not ideal for
calibration. Calibration should be
attempted on an alternate road surface.
.The accessory trailer cameras are
swapped at the hitch connector. Ensure
that the camera mounted to the rear of
the trailer is connected to the rear trailer
camera input.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
274 Driving and Operating
The instrument cluster may have a Park
Assist display with bars that show“distance
to object” and object location information
for the Front and Rear Park Assist system.
As the object gets closer, more bars light up
and the bars change color from yellow to
amber to red.
When an object is first detected in the rear,
one beep will be heard from the rear,
or both sides of the Safety Alert Seat will
pulse two times. When an object is very
close —<0.4 m (1.5 ft) in the vehicle rear or
<0.3 m (1 ft) in the vehicle front —a
continuous beep will sound from the rear or
front depending on object location, or both
sides of the Safety Alert Seat will pulse five
times. Beeps for FPA are higher pitched than
for RPA.
Rear Cross Traffic Alert (RCTA)
If equipped, when the vehicle is shifted into
R (Reverse), RCTA shows a red warning
triangle with a left or right pointing arrow
on the infotainment display to warn of
traffic coming from the left or right. This
system detects objects coming from up to
20 m (65 ft) from the left or right side of
the vehicle. When an object is detected,
either three beeps sound from the left or right or three Safety Alert Seat pulses occur
on the left or right side, depending on the
direction of the detected vehicle.
Use caution while backing up when towing
a trailer, as the RCTA detection zones that
extend out from the back of the vehicle do
not move further back when a trailer is
towed.
RCTA is disabled when the trailer connection
status is displayed.
RCTA can be turned off. See
“Collision/
Detection Systems” underVehicle
Personalization 0131.
Turning the Features On or Off
PressXon the center stack to turn on or
off the Front and Rear Park Assist. The
indicator light next to the button comes on
when the features are on and turns off
when the features have been disabled. Front and Rear Park Assist can be turned
Off, On, or On with Towbar. See
“Park
Assist” underVehicle Personalization 0131.
If Park Assist is turned off through vehicle
personalization, the Park Assist button will
be disabled. To turn Park Assist on again,
select On in vehicle personalization. The On
with Towbar setting allows Park Assist to
work properly with a trailer hitch. Some
larger trailer hitches may not be compatible.
Turn off Park Assist when towing a trailer.
To turn the RPA symbols on or off, see
“Rear Camera Park Assist Symbols” under
Vehicle Personalization 0131.
Assistance Systems for Driving
If equipped, when driving the vehicle in a
forward gear, Forward Collision Alert (FCA),
Lane Departure Warning (LDW), Lane Keep
Assist (LKA), Side Blind Zone Alert (SBZA),
Lane Change Alert (LCA), Automatic
Emergency Braking (AEB), and/or the Front
Pedestrian Braking (FPB) System can help to
avoid a crash or reduce crash damage.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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278 Driving and Operating
AEB and IBA can be disabled. See“Collision/
Detection Systems” underVehicle
Personalization 0131.
{Warning
Using AEB or IBA while towing a trailer
could cause you to lose control of the
vehicle and crash. Turn the system to
Alert or Off when towing a trailer.
A system unavailable message may
display if:
.The front of the vehicle or windshield is
not clean.
.Heavy rain or snow is interfering with
object detection.
.There is a problem with the StabiliTrak/
Electronic Stability Control (ESC) system.
The AEB system does not need service.
Front Pedestrian Braking (FPB)
System
If equipped, the FPB system may help avoid
or reduce the harm caused by front-end
crashes with nearby pedestrians when
driving in a forward gear. FPB displays an
amber indicator,
~, when a nearby
pedestrian is detected ahead. When approaching a detected pedestrian too
quickly, FPB provides a red flashing alert on
the windshield and rapidly beeps or pulses
the driver seat. FPB can provide a boost to
braking or automatically brake the vehicle.
This system includes Intelligent Brake Assist
(IBA), and the Automatic Emergency Braking
(AEB) system may also respond to
pedestrians. See
Automatic Emergency
Braking (AEB) 0277.
The FPB system can detect and alert to
pedestrians in a forward gear at speeds
between 8 km/h (5 mph) and 80 km/h
(50 mph). During daytime driving, the
system detects pedestrians up to a distance
of approximately 40 m (131 ft). During
nighttime driving, system performance is
very limited.
{Warning
FPB does not provide an alert or
automatically brake the vehicle, unless it
detects a pedestrian. FPB may not detect
pedestrians, including children:
.When the pedestrian is not directly
ahead, fully visible, or standing
upright, or when part of a group. (Continued)
Warning (Continued)
.Due to poor visibility, including
nighttime conditions, fog, rain,
or snow.
.If the FPB sensor is blocked by dirt,
snow, or ice.
.If the headlamps or windshield are not
cleaned or in proper condition.
Be ready to take action and apply the
brakes. For more information, see
Defensive Driving 0213. Keep the
windshield, headlamps, and FPB sensor
clean and in good repair.
FPB can be set to Off, Alert, or Alert and
Brake through vehicle personalization. See
“Collision/Detection Systems” underVehicle
Personalization 0131.
Detecting the Pedestrian Ahead

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 279
FPB alerts and automatic braking will not
occur unless the FPB system detects a
pedestrian. When a nearby pedestrian is
detected in front of the vehicle, the
pedestrian ahead indicator will display
amber.
Front Pedestrian Alert
With Head-Up Display
Without Head-Up Display
When the vehicle approaches a pedestrian
ahead too rapidly, the red FPB alert display
will flash on the windshield. Eight rapid
high-pitched beeps will sound from the
front, or both sides of the Safety Alert Seat
will pulse five times. When this Pedestrian Alert occurs, the brake system may prepare
for driver braking to occur more rapidly
which can cause a brief, mild deceleration.
Continue to apply the brake pedal as
needed. Cruise control may be disengaged
when the Front Pedestrian Alert occurs.
Automatic Braking
If FPB detects it is about to crash into a
pedestrian directly ahead, and the brakes
have not been applied, FPB may
automatically brake moderately or brake
hard. This can help to avoid some very low
speed pedestrian crashes or reduce
pedestrian injury. FPB can automatically
brake to detected pedestrians between
8 km/h (5 mph) and 80 km/h (50 mph).
Automatic braking levels may be reduced
under certain conditions, such as higher
speeds.
If this happens, Automatic Braking may
engage the Electric Parking Brake (EPB) to
hold the vehicle at a stop. Release the EPB.
A firm press of the accelerator pedal will
also release Automatic Braking and the EPB.
{Warning
FPB may alert or automatically brake the
vehicle suddenly in situations where it is
unexpected and undesired. It could falsely
alert or brake for objects similar in shape
or size to pedestrians, including shadows.
This is normal operation and the vehicle
does not need service. To override
Automatic Braking, firmly press the
accelerator pedal, if it is safe to do so.
Automatic Braking can be disabled through
vehicle personalization. See “Front Pedestrian
Detection” in“Collision/Detection Systems”
under Vehicle Personalization 0131.
{Warning
Using the Front Pedestrian Braking
system while towing a trailer could cause
you to lose control of the vehicle and
crash. Turn the system to Alert or Off
when towing a trailer.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 281
When the vehicle is started, both outside
mirror LCA displays will briefly come on to
indicate the system is operating. When the
vehicle is in a forward gear, the left or right
side mirror display will light up if a moving
vehicle is detected in the next lane over in
that blind zone or rapidly approaching that
zone. If the turn signal is activated in the
same direction as a detected vehicle, this
display will flash as an extra warning not to
change lanes.
LCA can be disabled through vehicle
personalization. When you disable LCA, SBZA
is also disabled. SeeVehicle Personalization
0 131. If LCA is disabled by the driver, the
LCA mirror displays will not light up.
When the System Does Not Seem to
Work Properly
The LCA system requires some driving for
the system to calibrate to maximum
performance. This calibration may occur
more quickly if the vehicle is driving on a
straight highway road with traffic and
roadside objects (e.g., guardrails, barriers).
LCA displays may not come on when
passing a vehicle quickly, for a stopped
vehicle, or when towing a trailer. The LCA
detection zones that extend back from the side of the vehicle do not move further back
when a trailer is towed. Use caution while
changing lanes when towing a trailer. LCA
may alert to objects attached to the vehicle,
such as a trailer, bicycle, or object extending
out to either side of the vehicle. Attached
objects may also interfere with the
detection of vehicles. This is normal system
operation; the vehicle does not need service.
LCA may not always alert the driver to
vehicles in the next lane over, especially in
wet conditions or when driving on sharp
curves. The system does not need to be
serviced. The system may light up due to
guardrails, signs, trees, shrubs, and other
non-moving objects. This is normal system
operation; the vehicle does not need service.
LCA may not operate when the LCA sensors
in the left or right corners of the rear
bumper are covered with mud, dirt, snow,
ice, or slush, or in heavy rainstorms. For
cleaning instructions, see "Washing the
Vehicle" under
Exterior Care0398. If the
DIC still displays the system unavailable
message after cleaning both sides of the
vehicle toward the rear corners of the
vehicle, see your dealer. If the LCA displays do not light up when
moving vehicles are in the side blind zone or
are rapidly approaching this zone and the
system is clean, the system may need
service. Take the vehicle to your dealer.
Radio Frequency Information
See
Radio Frequency Statement 0436.
Lane Keep Assist (LKA)
If equipped, LKA may help avoid crashes due
to unintentional lane departures. This
system uses a camera to detect lane
markings between 60 km/h (37 mph) and
180 km/h (112 mph). It may assist by gently
turning the steering wheel if the vehicle
approaches a detected lane marking. It may
also provide a Lane Departure Warning
(LDW) alert if the vehicle crosses a detected
lane marking. LKA can be overridden by
turning the steering wheel. This system is
not intended to keep the vehicle centered in
the lane. LKA will not assist and alert if the
turn signal is active in the direction of lane
departure, or if it detects that you are
accelerating, braking or actively steering.

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282 Driving and Operating
{Warning
The LKA system does not continuously
steer the vehicle. It may not keep the
vehicle in the lane or give a Lane
Departure Warning (LDW) alert, even if a
lane marking is detected.
The LKA and LDW systems may not:
.Provide an alert or enough steering
assist to avoid a lane departure or
crash.
.Detect lane markings under poor
weather or visibility conditions. This
can occur if the windshield or
headlamps are blocked by dirt, snow,
or ice; if they are not in proper
condition; or if the sun shines directly
into the camera.
.Detect road edges.
.Detect lanes on winding or hilly roads.
If LKA only detects lane markings on one
side of the road, it will only assist or
provide an LDW alert when approaching
the lane on the side where it has
detected a lane marking. Even with LKA
and LDW, you must steer the vehicle. (Continued)
Warning (Continued)
Always keep your attention on the road
and maintain proper vehicle position
within the lane, or vehicle damage,
injury, or death could occur. Always keep
the windshield, headlamps, and camera
sensors clean and in good repair. Do not
use LKA in bad weather conditions or on
roads with unclear lane markings, such as
construction zones.
{Warning
Using LKA while towing a trailer or on
slippery roads could cause loss of control
of the vehicle and a crash. Turn the
system off.
How the System Works
LKA uses a camera sensor installed on the
windshield ahead of the rearview mirror to
detect lane markings. It may provide brief
steering assist if it detects an unintended
lane departure. It may further provide an
audible alert or the driver seat may pulse
indicating that a lane marking has been
crossed. To turn LKA on and off, press
Aon the
center stack. If equipped, the indicator light
on the button comes on when LKA is on and
turns off when LKA is disabled.
When on,
Ais white, if equipped,
indicating that the system is not ready to
assist.
Ais green if LKA is ready to
assist. LKA may assist by gently turning the
steering wheel if the vehicle approaches a
detected lane marking.
Ais amber when
assisting. It may also provide a Lane
Departure Warning (LDW) alert by flashing
Aamber if the vehicle crosses a
detected lane marking. Additionally, there
may be three beeps, or the driver seat may
pulse three times, on the right or left,
depending on the lane departure direction.
Take Steering
The LKA system does not continuously steer
the vehicle. If LKA does not detect active
driver steering, an alert and chime may be
provided. Steer the vehicle to dismiss. LKA
may become temporarily unavailable after
repeated take steering alerts.