
Black plate (54,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
9-54 Driving and Operating
Reducing Speed While ACC is at a
Set Speed
If ACC is already activated, do one
of the following:
.Use the brake to get to the
desired lower speed. Press
SET–and release the
accelerator pedal. The vehicle
will now cruise at the lower
speed.
.Press and hold SET– until the
desired lower speed is reached,
then release it.
.To decrease the vehicle speed in
small increments, briefly press
SET−. For each press, the
vehicle speed goes to the next
5 km/h (1 mph) slower mark on
the speedometer.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster on
page 5-10. The increment value
used depends on the units
displayed. Selecting the Follow Distance Gap
When a slower moving vehicle is
detected ahead within the selected
following gap, ACC will adjust the
vehicle's speed and attempt to
maintain the follow distance gap
selected.
Press
3on the steering wheel to
adjust the following gap. When
pressed, the current gap setting
displays briefly on the instrument
cluster. Subsequent presses cycle
the
3button through three
settings: Far, Medium, or Near. The
gap setting will be maintained until it
is changed.
Since each gap setting corresponds
to a following time (Far, Medium,
or Near), the following distance will
vary based on vehicle speed. The
faster the vehicle speed, the further
back your vehicle will follow a
vehicle detected ahead. Consider
traffic and weather conditions when
selecting the following gap. The range of selectable gaps may not be
appropriate for all drivers and
driving conditions.
Changing the gap setting
automatically changes the alert
timing sensitivity (Far, Medium,
or Near) for the Forward Collision
Alert (FCA) feature. See
Forward
Collision Alert (FCA) System on
page 9-62.
Alerting the Driver
If ACC is engaged, driver action
may be required when ACC cannot
apply sufficient braking because of
approaching a vehicle too rapidly.
When this condition occurs, six red
lights will flash on the windshield,
and either eight beeps will sound
from the front, or both sides of the
Safety Alert Seat will pulse five

Black plate (55,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-55
times. See“Collision/Detection
Systems” underVehicle
Personalization on page 5-43.
See Defensive Driving on page 9-3.
Approaching and Following a
Vehicle
The vehicle ahead symbol is in the
instrument cluster.
The vehicle ahead symbol only
displays when a vehicle is detected
in your vehicle’s path moving in the
same direction.
If this symbol is not displaying, ACC
will not respond to or brake to
vehicles ahead.
ACC automatically slows the vehicle
down and adjusts vehicle speed to
follow the vehicle in front at the
selected follow gap. The vehicle speed increases or decreases to
follow the vehicle in front of you, but
will not exceed the set speed. It may
apply limited braking, if necessary.
When braking is active, the brake
lights will come on. The automatic
braking may feel or sound different
than if the brakes were applied
manually. This is normal.
Stationary or Very Slow-Moving
Objects
{Warning
Adaptive Cruise Control (ACC)
may not detect and react to
stopped or slow-moving vehicles
ahead of you. For example, the
system may not brake for a
vehicle that it has never detected
moving. This can occur in
stop-and-go traffic or when a
vehicle suddenly appears due to
a vehicle ahead changing lanes.
Your vehicle may not stop and
could cause a crash. Use caution
(Continued)
Warning (Continued)
when using ACC. Your complete
attention is always required while
driving and you should be ready
to take action and apply the
brakes.
ACC Automatically Disengages
ACC may automatically disengage
and the driver will need to manually
apply the brakes to slow the
vehicle when:
.Your vehicle speed goes below
the minimum speed of 25 km/h
(16 mph).
.The sensors are blocked.
.The Traction Control System
(TCS) or electronic stability
control system has activated or
been disabled.
.No traffic or other objects are
being detected.
.There is a fault in the system.

Black plate (57,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-57
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, signs, guardrails, and other
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.
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. The
driver will often need to take over
acceleration and braking on steep
hills, especially when towing a
trailer. If the brakes are applied, the
ACC disengages.
Disengaging ACC
There are three ways to
disengage ACC:
.Step lightly on the brake pedal.
.Press*.
.Press5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5is pressed
or if the ignition is turned off.

Black plate (61,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-61
The vehicle may have an instrument
cluster parking assist display with
bars that show“distance to object”
and object location information for
RPA, and on some vehicles, for the
FPA system. As the object gets
closer, more bars light up.
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
(<0.6 m (2 ft) in the vehicle rear,
or <0.3 m (1 ft) in the vehicle front),
a continuous beep will sound from
the front or rear, or both sides of the Safety Alert Seat will pulse five
times. Beeps for FPA are higher
pitched than for RPA.
Turning the Features On or Off
TheXbutton to the left of the
steering wheel is used to turn on or
off the Front and Rear Parking
Assist. The indicator light in the
button comes on when the features
are on and turns off when the
features have been disabled.
Front and Rear Parking Assist can
be turned off, on, or on with towbar
through vehicle personalization.
See “Parking Assist” underVehicle
Personalization on page 5-43. If the
parking assist is turned off through
vehicle personalization, the park
assist button will be disabled. To turn the parking assist on again,
select On in the vehicle
personalization menu. The On with
Towbar setting allows for the
parking assist to work properly with
a small item attached to the trailer
hitch. Turn off parking assist when
towing a trailer.
To turn the rear parking assist
symbols, RCTA, or guidance lines
on or off:
1. On the infotainment system
Home screen, press the Settings
screen button, or turn the MENU
knob to highlight Settings and
press MENU.
2. Select Rear Camera.
3. Press Rear Park Assist Symbols, Rear Cross Traffic
Alert, or Guidance Lines and
then select Off or On.

Black plate (62,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
9-62 Driving and Operating
Assistance Systems for
Driving
If equipped, when driving the
vehicle forward, Forward Collision
Alert (FCA), Lane Departure
Warning (LDW), Side Blind Zone
Alert (SBZA), Lane Change Alert
(LCA), and/or the Active Emergency
Braking 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 speedsabove 40 km/h (25 mph). If the
vehicle has Adaptive Cruise Control
(ACC), it can detect vehicles to
distances of approximately 110 m
(360 ft) and operates at all speeds.
See
Adaptive Cruise Control on
page 9-51.
{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. FCA does not warn
of pedestrians, animals, signs,
guardrails, bridges, construction
barrels, or other objects. Be ready
to take action and apply the
brakes. For more information, see
Defensive Driving on page 9-3. FCA can be disabled with the FCA
steering wheel control, or if your
vehicle is equipped with Adaptive
Cruise Control (ACC), through
vehicle personalization. See the
“Auto Collision Preparation”
portion
of “Collision/Detection Systems”
under Vehicle Personalization on
page 5-43.Detecting the Vehicle Ahead
FCA warnings will not occur unless
the FCA system detects a vehicle
ahead. When the vehicle is
detected, the vehicle-ahead
indicator will display green. Vehicles
may not be detected on curves,
highway exit ramps, or hills; or due
to poor visibility. FCA will not detect
another vehicle ahead until it is
completely in the driving lane.

Black plate (65,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-65
Warning (Continued)
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.
Brake Preparation
When quickly approaching a vehicle
ahead, Brake Preparation reduces
brake response time by having the
brake system prepared for driver
braking to occur more rapidly.
Automatic Braking
In some imminent front-end crash
situations, if the driver has not
applied the brakes, Automatic
Braking applies the brakes to help
reduce crash damage. It may even
help avoid some very low speed
crashes.
Automatic Braking may slow the
vehicle to a complete stop to try to
avoid a potential crash. The vehicle will only hold at a stop briefly. A firm
press of the accelerator pedal will
also release Automatic Braking.
{Warning
Automatic Braking may
automatically brake the vehicle in
situations where it may be
unnecessary. It could respond to
a turning vehicle ahead,
guardrails, signs, and other
non-moving objects. This could
be uncomfortable and startling. To
override Automatic Braking, firmly
press the accelerator pedal, if it is
safe to do so.
Automatic Braking can be disabled
or reduced through vehicle
personalization. See the “Auto
Collision Preparation” portion of
“Collision/Detection Systems” under
Vehicle Personalization on
page 5-43.
{Warning
Using the Automatic Collision
Preparation System while towing
a trailer could cause you to lose
control of the vehicle and crash.
Turn the system off when towing
a trailer.
Side Blind Zone
Alert (SBZA)
If equipped, the SBZA system is a
lane-changing aid that assists
drivers with avoiding crashes that
occur with vehicles in the side blind
zone (or spot) areas. When the
vehicle is moving forward, the left-
or right-side mirror display will light
up if a 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

Black plate (66,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
9-66 Driving and Operating
Change Alert system, please read
the entire Lane Change Alert
section before using this feature.
Lane Change Alert
If equipped, the LCA system is a
lane-changing aid that assists
drivers with avoiding lane change
crashes that occur with 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
provide alerts when changing
lanes under all driving conditions.
Failure to use proper care when
changing lanes may result in(Continued)
Warning (Continued)
injury, death, or vehicle damage.
Before making a lane change,
always check mirrors, glance over
your shoulder, and use the turn
signals.
1. SBZA Detection Zone
2. LCA Detection Zone
LCA Detection Zones
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 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
70 m (230 ft) behind the vehicle.
How the System Works
The LCA symbol lights up in the
side mirrors when the system
detects a vehicle in the next lane
over that is in the side blind zone or
rapidly approaching 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

Black plate (67,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-67
When the vehicle is started, both
outside mirror LCA displays will
briefly come on to indicate the
system is operating. When the
vehicle is moving forward, the left-
or right-side mirror display will light
up if a 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. See
“Collision/Detection Systems”under
Vehicle Personalization on
page 5-43. 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 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 Care on
page 10-86. 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 vehicles are in the side blind
zone or rapidly approaching this
zone and the system is clean, the
system may need service. Take the
vehicle to your dealer.
When LCA is disabled for any
reason other than the driver turning
it off, the Side Blind Zone Alert On
option will not be available on the
personalization menu.