2020 GMC SIERRA DENALI warning

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
268 Driving and Operating
Front and Rear Park Assist can be
turned Off, On, or On with Towbar.
See“Park Assist” underVehicle
Personalization 0156. 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 0156.
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 0156.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
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/
Mexico-13337776) - 2020 - CRC - 8/27/19
Driving and Operating 271
moderately or hard. This automatic
emergency braking can only occur if
a vehicle is detected. This is shown
by the FCA vehicle ahead indicator
being lit. SeeForward Collision Alert
(FCA) System 0268.
The system works when driving in a
forward gear between 8 km/h
(5 mph) and 80 km/h (50 mph).
It can detect vehicles up to
approximately 60 m (197 ft).
{Warning
AEB is an emergency crash
preparation feature and is not
designed to avoid crashes. Do
not rely on AEB to brake the
vehicle. AEB will not brake
outside of its operating speed
range and only responds to
detected vehicles.
AEB may not: . Detect a vehicle ahead on
winding or hilly roads.
(Continued)
Warning (Continued)
.Detect all vehicles,
especially vehicles with a
trailer, tractors, muddy
vehicles, etc.
. Detect a vehicle when
weather limits visibility, such
as in fog, rain, or snow.
. Detect a vehicle ahead if it
is partially blocked by
pedestrians or other objects.
Complete attention is always
required while driving, and you
should be ready to take action
and apply the brakes and/or steer
the vehicle to avoid crashes.
AEB may slow the vehicle to a
complete stop to try to avoid a
potential crash. If this happens, AEB
may engage the Electric Parking
Brake (EPB) to hold the vehicle at a
stop. Release the EPB or firmly
press the accelerator pedal.
{Warning
AEB may automatically brake the
vehicle suddenly in situations
where it is unexpected and
undesired. It could respond to a
turning vehicle ahead, guardrails,
signs, and other non-moving
objects. To override AEB, firmly
press the accelerator pedal, if it is
safe to do so.
Intelligent Brake Assist (IBA)
IBA may activate when the brake
pedal is applied quickly by providing
a boost to braking based on the
speed of approach and distance to
a vehicle ahead.
Minor brake pedal pulsations or
pedal movement during this time is
normal and the brake pedal should
continue to be applied as needed.
IBA will automatically disengage
only when the brake pedal is
released.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
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 0156.
{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)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
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 0156.
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/
Mexico-13337776) - 2020 - CRC - 8/27/19
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 0156.
{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)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Driving and Operating 275
Warning (Continued)
provide alerts when changing
lanes under all driving conditions.
Failure to use proper care when
changing lanes may result in
injury, death, or vehicle damage.
Before making a lane change,
always check mirrors, glance over
your shoulder, and use the turn
signals.
LCA Detection Zones
1. SBZA Detection Zone
2. LCA Detection Zone
The LCA sensor covers a zone of
approximately one lane over from
both sides of the vehicle, or 3.5 m
(11 ft). The height of the zone is
approximately between 0.5 m (1.5 ft)
and 2 m (6 ft) off the ground. The
Side Blind Zone Alert (SBZA)
warning area starts at approximately
the middle of the vehicle and goes
back 5 m (16 ft). Drivers are also
warned of vehicles rapidly
approaching from up to 25 m (82 ft)
behind the vehicle.
How the System Works
The LCA symbol lights up in the
side mirrors when the system
detects a moving vehicle in the next
lane over that is in the side blind
zone or rapidly approaching that
zone from behind. A lit LCA symbol
indicates it may be unsafe to
change lanes. Before making a lane
change, check the LCA display,
check mirrors, glance over your
shoulder, and use the turn signals.
Left Side Mirror DisplayRight Side Mirror Display
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 is disabled when the trailer
connection status is displayed.
A DIC message may display. The
SBZA system still operates.
LCA can be disabled through
vehicle personalization. When you
disable LCA, SBZA is also disabled.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
276 Driving and Operating
SeeVehicle Personalization 0156.
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 Care0429.
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
0 472.
Lane Departure Warning
(LDW) (2500/3500 Series)
If equipped, LDW may help avoid
crashes due to unintentional lane
departures. LDW uses a camera
sensor to detect the lane markings
at speeds of 56 km/h (35 mph) or
greater. It may provide an alert if the
vehicle is crossing a lane without
using a turn signal in that direction.
LDW light will not alert if the turn
signal is active in the direction of
lane departure, or if LDW detects
that you are accelerating, braking or
actively steering.