2021 GMC YUKON lane assist

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Driving and Operating 273
LCA Detection Zones
1. SBZA Detection Zone
2. LCA Detection Zone
When towing a trailer, LCA feature is
disabled. When not towing a trailer, 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. Drivers are also
warned of vehicles rapidly approaching this
area up to approximately 70 m (230 ft)
behind the vehicle.
Extended Side Blind Zone Area (ESBZA)
If equipped, the ESBZA system is a
lane-changing aid that assists drivers with
avoiding crashes that occur with moving
vehicles in the side blind zone, or blind spotareas. The extended side blind zone area
adds the blind zone area along the side of a
trailer that the host vehicle is pulling.
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
extended 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
system, read the entire Lane Change Alert
section before using this feature.
{Warning
ESBZA 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 injury, death, or vehicle
damage. Before making a lane change,
always check mirrors, glance over your
shoulder, and use the turn signals.
ESBZA Detection Zones
1. SBZA Detection Zone
2. ESBZA Detection Zone
3. LCA Detection Zone
The Side Blind Zone Alert (SBZA) warning
area starts at approximately the middle of
the vehicle and goes back 5 m (16 ft). The
Extended Side Blind Zone Alert (ESBZA)
warning area starts at approximately 3 m
(10 ft) to the trailing edge of the vehicle and
goes back up to 21 m (69 ft) behind the
vehicle. The maximum trailer length is
12 m (39 ft).
How the System Works
The LCA/ESBZA symbol lights up in the side
mirrors when the system detects a moving
vehicle in the next lane over that is in the
extended side blind zone. This indicates it
may be unsafe to change lanes. Before

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 275
Driving with a Trailer
Although this system is intended to help
drivers avoid lane change crashes, it does
not replace driver vision and therefore
should be considered a lane change aid.
Even with the ESBZA system, the driver
must check carefully for objects outside of
the reporting zone (e.g., a fast approaching
vehicle) or vehicle along the side of the
trailer before changing lanes.
Use caution while changing lanes when
towing a trailer.
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 theturn signal is active in the direction of lane
departure, or if it detects that you are
accelerating, braking, or actively steering.
{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 (Continued)
Warning (Continued)
the lane on the side where it has
detected a lane marking. Even with LKA
and LDW, you must steer the vehicle.
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

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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276 Driving and Operating
audible alert or the driver seat may pulse
indicating that a lane marking has been
crossed.
To turn LKA on and off, press
Ato the
left of the steering wheel. 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.
When the System Does Not Seem to
Work Properly
The system performance may be
affected by:
.Close vehicles ahead.
.Sudden lighting changes, such as when
driving through tunnels.
.Banked roads.
.Roads with poor lane markings, such as
two-lane roads.
If the LKA system is not functioning
properly when lane markings are clearly
visible, cleaning the windshield may help.
A camera blocked message may display if
the camera is blocked. Some driver
assistance systems may have reduced
performance or not work at all. An LKA or
LDW unavailable message may display if the
systems are temporarily unavailable. This
message could be due to a blocked camera.
The LKA system does not need service. Clean
the outside of the windshield behind the
rearview mirror.
LKA assistance and/or LDW alerts may occur
due to tar marks, shadows, cracks in the
road, temporary or construction lane
markings, or other road imperfections. This is normal system operation; the vehicle does
not need service. Turn LKA off if these
conditions continue.
Fuel
Top Tier Fuel
GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine clean,
reduce engine deposits, and maintain
optimal vehicle performance. Look for the
TOP TIER Logo or see www.toptiergas.com
for a list of TOP TIER Detergent Gasoline
marketers and applicable countries.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
280 Driving and Operating
Trailer Towing
General Towing Information
Only use towing equipment that has been
designed for the vehicle. Contact your dealer
or trailering dealer for assistance with
preparing the vehicle to tow a trailer. Read
the entire section before towing a trailer.
To tow a disabled vehicle, seeTowing the
Vehicle 0370. To tow the vehicle behind
another vehicle such as a motor home, see
Recreational Vehicle Towing 0371.
Driving Characteristics and
Towing Tips
{Warning
You can lose control when towing a
trailer if the correct equipment is not
used or the vehicle is not driven properly.
For example, if the trailer is too heavy or
the trailer brakes are inadequate for the
load, the vehicle may not stop as
expected. You and others could be
seriously injured. The vehicle may also be
damaged, and the repairs would not be
covered by the vehicle warranty. Pull a
(Continued)
Warning (Continued)
trailer only if all the steps in this section
have been followed. Ask your dealer for
advice and information about towing a
trailer with the vehicle.
Driving with a Trailer
Trailering is different than just driving the
vehicle by itself. Trailering means changes in
handling, acceleration, braking, durability,
and fuel economy. Successful, safe trailering
takes correct equipment, and it has to be
used properly.
The following information has many
time-tested, important trailering tips and
safety rules. Many of these are important
for your safety and that of your passengers.
Read this section carefully before pulling a
trailer.
When towing a trailer:
.Become familiar with and follow all state
and local laws that apply to trailer
towing. These requirements vary from
state to state.
.State laws may require the use of
extended side view mirrors. Even if not
required, you should install extended side
view mirrors if your visibility is limited or
restricted while towing.
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to prevent
damage to the engine, axle, or other
parts.
.It is recommended to perform the first oil
change before heavy towing.
.During the first 800 km (500 mi) of trailer
towing, do not drive over 80 km/h
(50 mph) and do not make starts at full
throttle.
.Vehicles can tow in D (Drive). Tow/Haul
Mode is recommended for heavier trailers.
SeeTow/Haul Mode 0235. If the
transmission downshifts too often, a
lower gear may be selected using Manual
Mode. See Manual Mode 0235.
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

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 281
.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
When towing a trailer, exhaust gases
may collect at the rear of the vehicle and
enter if the liftgate, trunk/hatch,
or rear-most window is open. (Continued)
Warning (Continued)
When towing a trailer:
.Do not drive with the liftgate, trunk/
hatch, or rear-most window open.
.Fully open the air outlets on or under
the instrument panel.
.Also 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 0231.
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 be all be rated to carry the
intended cargo. Inadequate trailer
equipment can cause the combination to
operate in an unexpected or unsafe manner.
Before driving, inspect all trailer hitch parts
and attachments, safety chains, electrical connectors, lamps, tires, and mirrors. See
Towing Equipment
0287. If the trailer has
electric brakes, start the combination
moving and then manually apply the trailer
brake controller to check the trailer brakes
work. During the trip, occasionally check
that the cargo and trailer are secure and
that the lamps and any trailer brakes are
working.
Towing with a Stability Control System
When towing, the stability control system
might be heard. The system reacts to
vehicle movement caused by the trailer,
which mainly occurs during cornering. This is
normal when towing heavier trailers.
Following Distance
Stay at least twice as far behind the vehicle
ahead as you would when driving without a
trailer. This can help to avoid heavy braking
and sudden turns.
Passing
More passing distance is needed when
towing a trailer. The combination of the
vehicle and trailer will not accelerate as
quickly and is much longer than the vehicle
alone. It is necessary to go much farther

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
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292 Driving and Operating
.White/Green: Back-up Lamps
.Red/Green: Battery Feed
.Dark Blue: Trailer Brake
To help charge a remote (non-vehicle)
battery change drive mode to Tow Haul.
If the trailer is too light for Tow/Haul Mode,
turn on the headlamps to help charge the
battery.
Electric Brake Control Wiring Provisions
These wiring provisions are included with
the vehicle as part of the trailer wiring
package. These provisions are for an electric
brake controller.
The harness should be installed by your
dealer or a qualified service center.
Refer to the aftermarket electric trailer brake
controller owner's manual to determine wire
color coding of the electric trailer brake
controller. The wire colors on the brake
controller may be different from the vehicle.
Trailer Lamps
Always check all trailer lamps are working at
the beginning of each trip, and periodically
on longer trips.
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals should will illuminate to indicate the
vehicle is turning, changing lanes,
or stopping. When towing a trailer, the
arrows on the instrument cluster will
illuminate even if the trailer is not properly
connected or the bulbs are burned out.
Tow/Haul Mode
For instructions on how to enter Tow/Haul
mode, see Tow/Haul Mode 0235.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load.
Tow/Haul Mode is designed to be most
effective when the vehicle and trailer
combined weight is at least 75% of the
vehicle's Gross Combined Weight Rating
(GCWR). See “Maximum Trailer Weight”
under Trailer Towing 0284.
Tow/Haul Mode is most useful when towing
a heavy trailer or carrying a large or
heavy load:
.through rolling terrain
.in stop-and-go traffic
.in busy parking lots Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and may result in unpleasant
engine and transmission driving
characteristics and reduced fuel economy.
Integrated Trailer Brake Control System
The vehicle may have an Integrated Trailer
Brake Control (ITBC) system for use with
electric trailer brakes or most electric over
hydraulic trailer brake systems. These
instructions apply to both types of electric
trailer brakes.
This symbol is on the Trailer Brake Control
Panel on vehicles with an ITBC system. The
power output to the trailer brakes is
proportional to the amount of vehicle
braking. This available power output to the
trailer brakes can be adjusted to a wide
range of trailering situations.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13690468) - 2021 - crc - 8/14/20
418 Index
IndexA
Accessories and Modifications . . . . . . . . . . . 309
Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . 229
Adaptive Cruise Control . . . . . . . . . . . . . . . . . . 253
Add-On Electrical Equipment . . . . . . . . . . . . . 306
Additional InformationOnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Additional Maintenance and Care . . . . . . . . 390
Adjustments Lumbar, Front Seats . . . . . . . . . . . . . . . . . . . . 40
Agreements Trademarks and License . . . . . . . . . . . . . . . 196
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . .318
Air Conditioning . . . . . . . . . . . . . . . . . . . . 204, 207
Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
Air Filter, Passenger Compartment . . . . . . . 209
Air Suspension Four Corner . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
How Does an Airbag Restrain? . . . . . . . . . . 64
Passenger Sensing System . . . . . . . . . . . . . . 66
What Makes an Airbag Inflate? . . . . . . . . . 64
What Will You See after an AirbagInflates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
When Should an Airbag Inflate? . . . . . . . . 63 Airbag System (cont'd)
Where Are the Airbags? . . . . . . . . . . . . . . . . 62
Airbags Adding Equipment to the Vehicle . . . . . . . 69
Passenger Status Indicator . . . . . . . . . . . . . 110
Readiness Light . . . . . . . . . . . . . . . . . . . . . . . . 109
Servicing Airbag-Equipped Vehicles . . . . . . 69
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Alarm Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . 25
Alert Lane Change . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Rear Pedestrian . . . . . . . . . . . . . . . . . . . . . . . . 266
Side Blind Zone (SBZA) . . . . . . . . . . . . . . . . . 272
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 340
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 340
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Antenna Multi-band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Antilock Brake System (ABS) . . . . . . . . . . . . . 240 Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Apple CarPlay and Android Auto . . . . . . . . . 186
Armrest Storage . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Assistance Program, Roadside . . . . . . . . . . . . 402
Assistance Systems for Driving . . . . . . . . . . 267

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13690468) - 2021 - crc - 8/14/20
Index 423
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204, 207
I
If the System Needs Service . . . . . . . . . . . . . . 175
Ignition Positions . . . . . . . . . . . . . . . . . . . . . . . . 226
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
IndicatorPedestrian Ahead . . . . . . . . . . . . . . . . . . . . . . . 115
Vehicle Ahead . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Infants and Young Children, Restraints . . . . .72
Information Publication Ordering . . . . . . . . . . . . . . . . . . . 406
Infotainment System . . . . . . . . . . . . . . . . . . . . 409 Rear Seat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . . . 104
Instrument Panel Storage Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Instrument Panel Overview . . . . . . . . . . . . . . . . 4
Interior Rearview Mirrors . . . . . . . . . . . . . . . . . 30
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 1, 142
J
Jump Starting - North America . . . . . . . . . . . 367
K
Keyless Entry Remote (RKE) System . . . . . . . . . . . . . . . . . . . . 8
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
L
Labeling, Tire Sidewall . . . . . . . . . . . . . . . . . . . .341
Lamps
Daytime Running (DRL) . . . . . . . . . . . . . . . . 136
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Exterior Controls . . . . . . . . . . . . . . . . . . . . . . . 134
Exterior Lamps Off Reminder . . . . . . . . . . 136
Exterior Lighting Battery Saver . . . . . . . . . 141
Malfunction Indicator (CheckEngine) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
On Reminder . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Lane Change Alert (LCA) . . . . . . . . . . . . . . . . . 272
Lane Keep Assist (LKA) . . . . . . . . . . . . . . . . . . . 275
Lane Keep Assist Light . . . . . . . . . . . . . . . . . . . . 114
Lap-Shoulder Belt . . . . . . . . . . . . . . . . . . . . . . . . . 56
LATCH System Replacing Parts after a Crash . . . . . . . . . . . 83
LATCH, Lower Anchors and Tethers for
Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Liftgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Lighting Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Illumination Control . . . . . . . . . . . . . . . . . . . 139
LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331 Lights
Airbag Readiness . . . . . . . . . . . . . . . . . . . . . . 109
Antilock Brake System (ABS)
Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Brake System Warning . . . . . . . . . . . . . . . . . 112
Charging System . . . . . . . . . . . . . . . . . . . . . . . 111
Check Engine (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Door Ajar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Driver Mode Control . . . . . . . . . . . . . . . . . . . . 116
Electric Parking Brake . . . . . . . . . . . . . . . . . . . 113
Electronic Stability Control (ESC), Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Coolant Temperature Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Oil Pressure . . . . . . . . . . . . . . . . . . . . . 118
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Four Corner Air Suspension . . . . . . . . . . . . . 117
Four-Wheel-Drive . . . . . . . . . . . . . . . . . . . . . . . 114
Front Fog Lamp . . . . . . . . . . . . . . . . . . . . . . . . . 119
High-Beam On . . . . . . . . . . . . . . . . . . . . . . . . . . 119
High/Low Beam Changer . . . . . . . . . . . . . . 136
Hill Descent Control . . . . . . . . . . . . . . . . . . . . 114
Lane Keep Assist . . . . . . . . . . . . . . . . . . . . . . . . 114
Low Fuel Warning . . . . . . . . . . . . . . . . . . . . . . 118
Seat Belt Reminders . . . . . . . . . . . . . . . . . . . 109
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119