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254 Driving and Operating
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
*.
. Press
J.
Erasing Speed Memory
The ACC set speed is erased from
memory if
Jis pressed or if the
ignition is turned off.
Weather Conditions Affecting ACC
If the interior temperature is
extremely high, the instrument
cluster may indicate that ACC is
temporarily unavailable. This can be
caused by extreme hot weather
conditions with direct sunlight on the
front camera. ACC will return to
normal operation once the cabin
temperature is lower.
Conditions that are associated with
low visibility, such as fog, rain,
snow, or road spray, may limit ACC
performance. Water droplets from
rain or snow that remain on the
windshield may also limit ACC’s
ability to detect objects.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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268 Driving and Operating
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 0157. 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” underVehicle
Personalization 0157.
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.
Forward Collision Alert
(FCA) System
If equipped, the FCA system may
help to avoid or reduce the harm
caused by front-end crashes. When
approaching a vehicle ahead too
quickly, FCA provides a red flashing
alert on the windshield and rapidly
beeps or pulses the driver seat.
FCA also lights an amber visual
alert if following another vehicle
much too closely.
FCA detects vehicles within a
distance of approximately 60 m
(197 ft) and operates at speeds
above 8 km/h (5 mph).
{Warning
FCA is a warning system and
does not apply the brakes. When
approaching a slower-moving or
stopped vehicle ahead too rapidly,
or when following a vehicle too
closely, FCA may not provide a
warning with enough time to help
avoid a crash. It also may not
provide any warning at all. FCA
does not warn of pedestrians,
animals, signs, guardrails,
bridges, construction barrels,
or other objects. Be ready to take
action and apply the brakes. See
Defensive Driving
0187.
FCA can be disabled through
vehicle personalization. See
“Collision/Detection Systems” under
Vehicle Personalization 0157.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Driving and Operating 269
Detecting the Vehicle Ahead
FCA warnings will not occur unless
the FCA system detects a vehicle
ahead. When a vehicle is detected,
the vehicle ahead indicator will
display green. Vehicles may not be
detected on curves, highway exit
ramps, or hills, due to poor visibility;
or if a vehicle ahead is partially
blocked by pedestrians or other
objects. FCA will not detect another
vehicle ahead until it is completely
in the driving lane.
{Warning
FCA does not provide a warning
to help avoid a crash, unless it
detects a vehicle. FCA may not
detect a vehicle ahead if the FCA
sensor is blocked by dirt, snow,(Continued)
Warning (Continued)
or ice, or if the windshield is
damaged. It may also not detect a
vehicle on winding or hilly roads,
or in conditions that can limit
visibility such as fog, rain,
or snow, or if the headlamps or
windshield are not cleaned or in
proper condition. Keep the
windshield, headlamps, and FCA
sensors clean and in good repair.
Collision Alert
With Head-Up Display
Without Head-Up Display
When your vehicle approaches
another detected vehicle too rapidly,
the red FCA display will flash on the
windshield. Also, eight rapid
high-pitched beeps will sound from
the front, or both sides of the Safety
Alert Seat will pulse five times.
When this Collision 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 Collision Alert
occurs.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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270 Driving and Operating
Tailgating Alert
The vehicle ahead indicator will
display amber when you are
following a vehicle ahead much too
closely.
Selecting the Alert Timing
The Collision Alert control is on the
steering wheel. Press
[to set the
FCA timing to Far, Medium, or Near.
The first button press shows the
current setting on the DIC.
Additional button presses will
change this setting. The chosen
setting will remain until it is changed
and will affect the timing of both the
Collision Alert and the Tailgating
Alert features. The timing of both
alerts will vary based on vehicle
speed. The faster the vehicle speed,
the farther away the alert will occur.
Consider traffic and weather
conditions when selecting the alert timing. The range of selectable alert
timings may not be appropriate for
all drivers and driving conditions.
If your vehicle is equipped with
Adaptive Cruise Control (ACC),
changing the FCA timing setting
automatically changes the following
gap setting (Far, Medium, or Near).
Following Distance Indicator
The following distance to a moving
vehicle ahead in your path is
indicated in following time in
seconds on the Driver Information
Center (DIC). The minimum
following time is 0.5 seconds away.
If there is no vehicle detected
ahead, or the vehicle ahead is out of
sensor range, dashes will be
displayed.
Unnecessary Alerts
FCA may provide unnecessary
alerts for turning vehicles, vehicles
in other lanes, objects that are not
vehicles, or shadows. These alerts
are normal operation and the
vehicle does not need service.
Cleaning the System
If the FCA system does not seem to
operate properly, this may correct
the issue:
.
Clean the outside of the
windshield in front of the
rearview mirror.
. Clean the entire front of the
vehicle.
. Clean the headlamps.
Automatic Emergency
Braking (AEB)
If the vehicle has Forward Collision
Alert (FCA), it also has AEB (1500
series only), which includes
Intelligent Brake Assist (IBA). When
the system detects a vehicle ahead
in your path that is traveling in the
same direction that you may be
about to crash into, it can provide a
boost to braking or automatically
brake the vehicle. This can help
avoid or lessen the severity of
crashes when driving in a forward
gear. Depending on the situation,
the vehicle may automatically brake
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272 Driving and Operating
{Warning
IBA may increase vehicle braking
in situations when it may not be
necessary. You could block the
flow of traffic. If this occurs, take
your foot off the brake pedal and
then apply the brakes as needed.
AEB and IBA can be disabled. See
“Collision/Detection Systems” under
Vehicle Personalization 0157.
{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 (1500
Series)
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) 0270. 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.
. Due to poor visibility,
including nighttime
conditions, fog, rain,
or snow.
. If the FPB sensor is blocked
by dirt, snow, or ice.
(Continued)
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Driving and Operating 273
Warning (Continued)
.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 0187.
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 0157.
Detecting the Pedestrian
Ahead
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 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
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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274 Driving and Operating
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 0157.
{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.
Cleaning the System
If FPB does not seem to operate
properly, cleaning the outside of the
windshield in front of the rearview
mirror may correct the issue.
Side Blind Zone
Alert (SBZA)
If equipped, the SBZA system is a
lane-changing aid that assists
drivers with avoiding crashes that
occur with moving vehicles in the
side blind zone (or spot) areas.
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 that blind
zone. If the turn signal is activated and a vehicle is also detected on
the same side, the display will flash
as an extra warning not to change
lanes. Since this system is part of
the Lane Change Alert (LCA)
system, read the entire LCA section
before using this feature.
Lane Change Alert (LCA)
If equipped, the LCA system is a
lane-changing aid that assists
drivers with avoiding lane change
crashes that occur with moving
vehicles in the side blind zone (or
spot) areas or with vehicles rapidly
approaching these areas from
behind. The LCA warning display
will light up in the corresponding
outside side mirror and will flash if
the turn signal is on.
{Warning
LCA does not alert the driver to
vehicles outside of the system
detection zones, pedestrians,
bicyclists, or animals. It may not
(Continued)
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288 Driving and Operating
.Vehicles can tow in D (Drive).
Tow/Haul Mode is recommended
for heavier trailers. See Tow/
Haul Mode 0226. If the
transmission downshifts too
often, a lower gear may be
selected using Manual Mode.
See Manual Mode 0224.
If equipped, the following driver
assistance features should be
turned off when towing a trailer:
. Adaptive Cruise Control (ACC)
. Super Cruise Control
. Lane Keep Assist (LKA)
. Park Assist
. Automatic Parking Assist (APA)
. Reverse Automatic
Braking (RAB)
If equipped, the following driver
assistance features should be
turned to alert or off when towing a
trailer:
. Automatic Emergency
Braking (AEB)
. Intelligent Brake Assist (IBA) .
Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert
(LCA), 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.
If equipped with Rear Cross Traffic
Alert (RCTA), 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.
{Warning
To prevent serious injury or death
from carbon monoxide (CO),
when towing a trailer: . Do not drive with the
liftgate, trunk/hatch,
or rear-most window open.
(Continued)
Warning (Continued)
.Fully open the air outlets on
or under the instrument
panel.
. Adjust the climate control
system to a setting that
brings in only outside air.
See “Climate Control
Systems” in the Index.
For more information about
carbon monoxide, see Engine
Exhaust 0220.
Towing a trailer requires experience.
The combination of the vehicle and
trailer is longer and not as
responsive as the vehicle itself. Get
used to the handling and braking of
the combination by driving on a
level road surface before driving on
public roads.
The trailer structure, the tires, and
the brakes must all be rated to carry
the intended cargo. Inadequate
trailer equipment can cause the
combination to operate in an