heater GMC YUKON 2020 Owner's Manual

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
54 Seats and Restraints
Heated and Ventilated
Front Seats
{Warning
If temperature change or pain to
the skin cannot be felt, the seat
heater may cause burns. To
reduce the risk of burns, use care
when using the seat heater,
especially for long periods of
time. Do not place anything on
the seat that insulates against
heat, such as a blanket, cushion,
cover, or similar item. This may
cause the seat heater to
overheat. An overheated seat
heater may cause a burn or may
damage the seat.
The buttons are on the center stack
below the climate control system. To
operate, the engine must be
running.
Press
Ito heat the driver or
passenger seatback only.
Press
Jto heat the driver or
passenger seat cushion and
seatback.
If equipped, press
Cto ventilate the
driver or passenger seat.
The indicator light on the button
comes on when this feature is on. Press the button once for the
highest setting. With each press of
the button, the seat will change to
the next lower setting, and then to
the off setting. The indicator lights
next to the buttons indicate three for
the highest setting and one for the
lowest. If the heated seats are on
high for an extended time, their level
may automatically be lowered.
The passenger seat may take
longer to heat up.
Remote Start Auto Heated and
Ventilated Seats
During a remote start, the heated or
ventilated seats can be turned on
automatically. When it is cold
outside, the heated seats turn on,
and when it is hot outside the
ventilated seats turn on. The heated
or ventilated seats are canceled
when the ignition is turned on. Press
the heated or ventilated seat button
to use the heated or ventilated seats
after the vehicle is started.
The heated or ventilated seat
indicator lights do not turn on during
a remote start.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Seats and Restraints 55
The temperature performance of an
unoccupied seat may be reduced.
This is normal.
The heated or ventilated seats will
not turn on during a remote start
unless they are enabled in the
vehicle personalization menu. See
Remote Vehicle Start023 and
Vehicle Personalization 0152.Rear Seats
Rear Seat Reminder
If equipped, the message REAR
SEAT REMINDER LOOK IN REAR
SEAT displays under certain
conditions indicating there may be
an item or passenger in the rear
seat. Check before exiting the
vehicle.
This feature will activate when a
second row door is opened while
the vehicle is on or up to 10 minutes
before the vehicle is turned on.
There will be an alert when the
vehicle is turned off. The alert does
not directly detect objects in the rear
seat; instead, under certain
conditions, it detects when a rear
door is opened and closed,
indicating that there may be
something in the rear seat.
The feature is active only once each
time the vehicle is turned on and off,
and will require reactivation by
opening and closing the second row
doors. There may be an alert even
when there is nothing in the rear
seat; for example, if a child entered the vehicle through the rear door
and left the vehicle without the
vehicle being shut off.
The feature can be turned on or off.
See
Vehicle Personalization 0152.
Heated Rear Seats
{Warning
If temperature change or pain to
the skin cannot be felt, the seat
heater may cause burns. See the
Warning under Heated and
Ventilated Front Seats 054.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
82 Seats and Restraints
Warning (Continued)
away. SeeAirbag Readiness
Light 0134 for more information,
including important safety
information.
If the On Indicator Is Lit for a
Child Restraint
The passenger sensing system is
designed to turn off the front
outboard passenger frontal airbag if
the system determines that an infant
is present in a child restraint. If a
child restraint has been installed
and the ON indicator is lit:
1. Turn the vehicle off.
2. Remove the child restraint from the vehicle.
3. Remove any additional items from the seat such as blankets,
cushions, seat covers, seat
heaters, or seat massagers.
4. Reinstall the child restraint following the directions
provided by the child restraint manufacturer and refer to
Securing Child Restraints (With
the Seat Belt in the Center
Front Seat)
0105 or
Securing Child Restraints (With
the Seat Belt in the Rear Seat)
0 103 or
Securing Child Restraints (With
the Seat Belt in the Front
Passenger Seat) 0106.
Make sure the seat belt
retractor is locked by pulling
the shoulder belt all the way
out of the retractor when
installing the child restraint,
even if the child restraint is
equipped with a seat belt lock
off. When the retractor lock is
set, the belt can be tightened
but not pulled out of the
retractor.
5. If, after reinstalling the child restraint and restarting the
vehicle, the ON indicator is still
lit, turn the vehicle off. Then
slightly recline the vehicle
seatback and adjust the seat
cushion, if adjustable, to make sure that the vehicle seatback
is not pushing the child
restraint into the seat cushion.
Also make sure the child
restraint is not trapped under
the vehicle head restraint.
If this happens, adjust the head
restraint. See
Head Restraints
0 47.
6. Restart the vehicle.
The passenger sensing system may
or may not turn off the airbag for a
child in a child restraint depending
upon the child’s size. It is better to
secure the child restraint in a rear
seat. Never put a rear-facing child
restraint in the front seat, even if the
ON indicator is not lit.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Seats and Restraints 83
If the Off Indicator Is Lit for an
Adult-Sized Occupant
If a person of adult size is sitting in
the front outboard passenger seat,
but the OFF indicator is lit, it could
be because that person is not sitting
properly in the seat or that the child
restraint locking feature is engaged.
Use the following steps to allow the
system to detect that person and
enable the front outboard passenger
frontal airbag:1. Turn the vehicle off. 2. Remove any additional material
from the seat, such as
blankets, cushions, seat
covers, seat heaters, or seat
massagers.
3. Place the seatback in the fully upright position.
4. Have the person sit upright in the seat, centered on the seat
cushion, with legs comfortably
extended.
5. If the shoulder portion of the belt is pulled out all the way,
the child restraint locking
feature will be engaged. This
may unintentionally cause the
passenger sensing system to
turn the airbag off for some
adult-sized occupants. If this
happens, unbuckle the belt, let
the belt go back all the way,
and then buckle the belt again
without pulling the belt out all
the way.
6. Restart the vehicle and have the person remain in this
position for two to three minutes
after the ON indicator is lit.
{Warning
If the front outboard passenger
airbag is turned off for an
adult-sized occupant, the airbag
will not be able to inflate and help
protect that person in a crash,
resulting in an increased risk of
serious injury or even death. An
adult-sized occupant should not
ride in the front outboard
passenger seat, if the passenger
airbag OFF indicator is lit.
Additional Factors Affecting
System Operation
Seat belts help keep the passenger
in position on the seat during
vehicle maneuvers and braking,
which helps the passenger sensing
system maintain the passenger
airbag status. See “Seat Belts”and
“Child Restraints” in the Index for
additional information about the
importance of proper restraint use.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
84 Seats and Restraints
A thick layer of additional material,
such as a blanket or cushion,
or aftermarket equipment such as
seat covers, seat heaters, and seat
massagers can affect how well the
passenger sensing system
operates. We recommend that you
not use seat covers or other
aftermarket equipment except when
approved by GM for your specific
vehicle. SeeAdding Equipment to
the Airbag-Equipped Vehicle 084
for more information about
modifications that can affect how
the system operates.
The ON indicator may be lit if an
object, such as a briefcase,
handbag, grocery bag, laptop,
or other electronic device, is put on
an unoccupied seat. If this is not
desired, remove the object from
the seat.
{Warning
Stowing articles under the
passenger seat or between the
passenger seat cushion and
(Continued)
Warning (Continued)
seatback may interfere with the
proper operation of the passenger
sensing system.
Servicing the
Airbag-Equipped Vehicle
Airbags affect how the vehicle
should be serviced. There are parts
of the airbag system in several
places around the vehicle. Your
dealer and the service manual have
information about servicing the
vehicle and the airbag system. To
purchase a service manual, see
Publication Ordering Information
0405.
{Warning
For up to 10 seconds after the
vehicle is turned off and the
battery is disconnected, an airbag
can still inflate during improper
service. You can be injured if you
(Continued)
Warning (Continued)
are close to an airbag when it
inflates. Avoid yellow connectors.
They are probably part of the
airbag system. Be sure to follow
proper service procedures, and
make sure the person performing
work for you is qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Adding accessories that change the
vehicle's frame, bumper system,
height, front end, or side sheet
metal may keep the airbag system
from working properly.
The operation of the airbag system
can also be affected by changing,
including improperly repairing or
replacing, any parts of the following:
.Airbag system, including airbag
modules, front or side impact
sensors, sensing and diagnostic
module, airbag wiring, or front
center console

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Seats and Restraints 85
.Front seats, including stitching,
seams or zippers
. Seat belts
. Steering wheel, instrument
panel, overhead console, ceiling
trim, or pillar garnish trim
. Inner door seals, including
speakers
Your dealer and the service manual
have information about the location
of the airbag modules and sensors,
sensing and diagnostic module, and
airbag wiring along with the proper
replacement procedures.
In addition, the vehicle has a
passenger sensing system for the
front outboard passenger position,
which includes sensors that are part
of the passenger's seat. The
passenger sensing system may not
operate properly if the original seat
trim is replaced with non-GM
covers, upholstery, or trim, or with
GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort enhancing pad
or device, installed under or on top of the seat fabric, could also
interfere with the operation of the
passenger sensing system. This
could either prevent proper
deployment of the passenger
airbag(s) or prevent the passenger
sensing system from properly
turning off the passenger airbag(s).
See
Passenger Sensing System
0 80.
If the vehicle has rollover roof-rail
airbags, see Different Size Tires
and Wheels 0344 for additional
important information.
If the vehicle must be modified
because you have a disability and
you have questions about whether
the modifications will affect the
vehicle's airbag system, or if you
have questions about whether the
airbag system will be affected if the
vehicle is modified for any other
reason, call Customer Assistance.
See Customer Assistance Offices
0 398.Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light 0134.
Caution
If an airbag covering is damaged,
opened, or broken, the airbag
may not work properly. Do not
open or break the airbag
coverings. If there are any
opened or broken airbag
coverings, have the airbag
covering and/or airbag module
replaced. For the location of the
airbags, see Where Are the
Airbags? 075. See your dealer
for service.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 183
Driving and
Operating
Driving Information
Driving for Better FuelEconomy . . . . . . . . . . . . . . . . . . . . 184
Distracted Driving . . . . . . . . . . . . 184
Defensive Driving . . . . . . . . . . . . . 185
Drunk Driving . . . . . . . . . . . . . . . . . 185
Control of a Vehicle . . . . . . . . . . . 186
Braking . . . . . . . . . . . . . . . . . . . . . . . 186
Steering . . . . . . . . . . . . . . . . . . . . . . 186
Off-Road Recovery . . . . . . . . . . . 187
Loss of Control . . . . . . . . . . . . . . . 187
Off-Road Driving . . . . . . . . . . . . . 188
Driving on Wet Roads . . . . . . . . 193
Hill and Mountain Roads . . . . . 193
Winter Driving . . . . . . . . . . . . . . . . 194
If the Vehicle Is Stuck . . . . . . . . 195
Vehicle Load Limits . . . . . . . . . . . 196
Starting and Operating
New Vehicle Break-In . . . . . . . . . 201
Adjustable Throttle and Brake Pedal . . . . . . . . . . . . . . . . . . . . . . . 201
Ignition Positions (Keyless Access) . . . . . . . . . . . . . . . . . . . . . 202 Ignition Positions (Key
Access) . . . . . . . . . . . . . . . . . . . . . 204
Starting the Engine . . . . . . . . . . . 206
Engine Heater . . . . . . . . . . . . . . . . 207
Retained Accessory Power (RAP) . . . . . . . . . . . . . . . . 209
Shifting Into Park . . . . . . . . . . . . . 209
Shifting out of Park . . . . . . . . . . . 210
Parking over Things That Burn . . . . . . . . . . . . . . . . . . . 211
Active Fuel Management . . . . . 211
Extended Parking . . . . . . . . . . . . . 211
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 212
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . . 212
Automatic Transmission
Automatic Transmission . . . . . . 213
Manual Mode . . . . . . . . . . . . . . . . . 216
Tow/Haul Mode . . . . . . . . . . . . . . . 218
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . 219
Brakes
Antilock Brake
System (ABS) . . . . . . . . . . . . . . . 224
Parking Brake . . . . . . . . . . . . . . . . 225
Brake Assist . . . . . . . . . . . . . . . . . . 225
Hill Start Assist (HSA) . . . . . . . . 225
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . . 226
Hill Descent Control (HDC) . . . 228
Magnetic Ride Control . . . . . . . . 229
Locking Rear Axle . . . . . . . . . . . . 229
Automatic Level Control . . . . . . 229
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . 230
Adaptive Cruise Control . . . . . . 232
Driver Assistance Systems
Driver Assistance Systems . . . 240
Assistance Systems for Parking or Backing . . . . . . . . . . 242
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . . 245
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . 245
Automatic Emergency Braking (AEB) . . . . . . . . . . . . . . . 248
Side Blind Zone Alert (SBZA) . . . . . . . . . . . . . . . . 249
Lane Change Alert (LCA) . . . . . 250
Lane Keep Assist (LKA) . . . . . . 251
Fuel
Top Tier Fuel . . . . . . . . . . . . . . . . . 254
Recommended Fuel (L83 5.3L V8 Engine) . . . . . . . . . . . . . . . . . . 254

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 207
to cool down. When the engine
starts, let go of the key and
accelerator. If the vehicle starts
briefly but then stops again, do
the same thing. This clears the
extra gasoline from the engine.
Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Starting Procedure (Keyless
Access)
1. With the Keyless Accesssystem, the RKE transmitter
must be in the vehicle. Press
ENGINE START/STOP with the
brake pedal applied. When the
engine begins cranking, let go
of the button.
The idle speed will go down as
the engine gets warm. Do not
race the engine immediately
after starting it.
If the RKE transmitter is not in
the vehicle, if there is
interference, or if the RKE battery is low, the Driver
Information Center (DIC) will
display a message.
Caution
Cranking the engine for long
periods of time, by trying to start
the engine immediately after
cranking has ended, can overheat
and damage the cranking motor,
and drain the battery. Wait at
least 15 seconds between each
try, to let the cranking motor
cool down.
2. If the engine does not start after five to 10 seconds,
especially in very cold weather
(below −18 °C or 0 °F), it could
be flooded with too much
gasoline. Try pushing the
accelerator pedal all the way to
the floor and holding it there as
you press ENGINE START/
STOP, for up to a maximum of
15 seconds. Wait at least
15 seconds between each try,
to allow the cranking motor to cool down. When the engine
starts, let go of the button, and
the accelerator. If the vehicle
starts briefly but then stops
again, do the same thing. This
clears the extra gasoline from
the engine. Do not race the
engine immediately after
starting it. Operate the engine
and transmission gently until
the oil warms up and lubricates
all moving parts.
Engine Heater
{Warning
Do not plug in the engine block
heater while the vehicle is parked
in a garage or under a carport.
Property damage or personal
injury may result. Always park the
vehicle in a clear open area away
from buildings or structures.
If equipped, the engine heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
208 Driving and Operating
at or below−18 °C (0 °F). Vehicles
with an engine heater should be
plugged in at least four hours before
starting. There may be an internal
thermostat in the plug end of the
cord, which will prevent engine
heater operation at temperatures
above −18 °C (0 °F).
To Use the Engine Heater
1. Turn off the engine.
2. Open the hood and unwrap the
electrical cord. The cord is by
the left front fender, next to the
engine compartment fuse
block.
Check the heater cord for
damage. If it is damaged, do
not use it. See your dealer for
a replacement. Inspect the
cord for damage yearly.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{Warning
Improper use of the heater cord
or an extension cord can damage
the cord and may result in
overheating and fire.
. Plug the cord into a
three-prong electrical utility
receptacle that is protected
by a ground fault detection
function. An ungrounded
outlet could cause an
electric shock.
. Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension
cord in good operating
condition, or using a
damaged heater or
extension cord, could make
(Continued)
Warning (Continued)
it overheat and cause a fire,
property damage, electric
shock, and injury.
. Do not operate the vehicle
with the heater cord
permanently attached to the
vehicle. Possible heater
cord and thermostat
damage could occur.
. While in use, do not let the
heater cord touch vehicle
parts or sharp edges. Never
close the hood on the
heater cord.
. Before starting the vehicle,
unplug the cord, reattach
the cover to the plug, and
securely fasten the cord.
Keep the cord away from
any moving parts.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep it

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 209
away from moving engine
parts. If you do not, it could be
damaged.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Retained Accessory
Power (RAP)
When the ignition is turned from on
to off, the following features (if
equipped) will continue to function
for up to 10 minutes, or until the
driver door is opened. These
features will also work when the
ignition is in RUN or ACC/
ACCESSORY:
. Infotainment System
. Power Windows (during RAP
this functionality will be lost
when any door is opened)
. Sunroof (during RAP this
functionality will be lost when
any door is opened)
. Auxiliary Power Outlet .
Audio System
. OnStar System
Shifting Into Park
{Warning
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle can
roll. If you have left the engine
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when you are on
fairly level ground, use the steps
that follow. If the vehicle has a
four-wheel-drive transfer case
with an N (Neutral) position, and
the transfer case is in N (Neutral),
the vehicle will be free to roll,
even if the shift lever is in
P (Park). Be sure the transfer
case is in a drive gear. If towing a
trailer, see Driving Characteristics
and Towing Tips 0259. 1. Hold the brake pedal down,
then set the parking brake. See
Parking Brake 0225.
2. Move the shift lever into the P (Park) position by pulling the
shift lever toward you and
moving it up as far as it will go.
3. Be sure the transfer case is in a drive gear –not in
N (Neutral).
4. Push the ignition key in, towards the steering column
and then turn the ignition off.
5. Remove the key and take it with you. If you can leave the
vehicle with the ignition key in
your hand, the vehicle is in
P (Park).
Leaving the Vehicle with the
Engine Running
{Warning
It can be dangerous to leave the
vehicle with the engine running.
The vehicle could move suddenly
(Continued)