
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Keys, Doors, and Windows 7
Keys, Doors, and
Windows
Keys and Locks
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Remote Keyless Entry (RKE) System . . . . . 8
Remote Keyless Entry (RKE) SystemOperation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Remote Vehicle Start . . . . . . . . . . . . . . . . . . . 14
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Power Door Locks . . . . . . . . . . . . . . . . . . . . . . . 16
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . 17
Automatic Door Locks . . . . . . . . . . . . . . . . . . . 17
Lockout Protection . . . . . . . . . . . . . . . . . . . . . . 17
Safety Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Doors
Liftgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Power Assist Steps . . . . . . . . . . . . . . . . . . . . . 25
Vehicle Security
Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . 25
Vehicle Alarm System . . . . . . . . . . . . . . . . . . 25
Steering Column Lock . . . . . . . . . . . . . . . . . . . 27
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Immobilizer Operation . . . . . . . . . . . . . . . . . . 27
Exterior Mirrors
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 28
Power Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Folding Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 29
Heated Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 30
Automatic Dimming Mirror . . . . . . . . . . . . . 30
Reverse Tilt Mirrors . . . . . . . . . . . . . . . . . . . . 30
Interior Mirrors
Interior Rearview Mirrors . . . . . . . . . . . . . . . 30
Manual Rearview Mirror . . . . . . . . . . . . . . . . 30
Automatic Dimming Rearview Mirror . . . 30
Rear Camera Mirror . . . . . . . . . . . . . . . . . . . . 30
Windows
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Power Windows . . . . . . . . . . . . . . . . . . . . . . . . 33
Sun Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Roof
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Keys and Locks
Keys
{Warning
Leaving children in a vehicle with a
remote key is dangerous and children or
others could be seriously injured or killed.
They could operate the power windows
or other controls or make the vehicle
move. The windows will function with
the remote key in the vehicle, and
children or others could be caught in the
path of a closing window. Do not leave
children in a vehicle with a remote key.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Keys, Doors, and Windows 15
The engine will turn off during a remote
vehicle start if:
.The coolant temperature gets too high.
.The oil pressure gets low.
The remote key range may be reduced
while the vehicle is running.
Other conditions can affect the performance
of the remote key. See Remote Keyless Entry
(RKE) System 08or
Vehicle Personalization 0126.
Starting the Engine Using Remote Start
1. Press
Stwice on the remote key. The
turn signal lamps will flash. The lamps
flash to confirm the request to remote
start the vehicle has been received.
During the remote start, the doors will
be locked and the parking lamps will
remain on as long as the engine is
running.
2. The engine will shut off after 15 minutes or after the remainder of the 30 minute
total running time is used, unless you
stop the remote start before engine
running has completed or the vehicle is
turned on.
3. Press the brake pedal and turn the ignition on to drive the vehicle. Extending Engine Run Time
Remote start can be used for up to
30 minutes of total engine run time.
After two remote starts of 15 minutes,
or multiple shorter time starts totaling
30 minutes have been used, the vehicle
must be started and then turned off before
the remote start can be used again.
Canceling a Remote Start
To cancel a remote start, do one of the
following:.Press and holdSuntil the parking
lamps turn off.
.Turn on the hazard warning flashers.
.Turn the ignition on and then off.
Door Locks
{Warning
Unlocked doors can be dangerous.
.Passengers, especially children, can
easily open the doors and fall out of a
moving vehicle. The doors can be
unlocked and opened while the vehicle
is moving. The chance of being thrown
out of the vehicle in a crash is (Continued)
Warning (Continued)
increased if the doors are not locked.
So, all passengers should wear seat
belts properly and the doors should be
locked whenever the vehicle is driven.
.Young children who get into unlocked
vehicles may be unable to get out.
A child can be overcome by extreme
heat and can suffer permanent injuries
or even death from heat stroke.
Always lock the vehicle whenever
leaving it.
.Outsiders can easily enter through an
unlocked door when you slow down
or stop the vehicle. Locking the doors
can help prevent this from happening.
To lock or unlock the doors from outside the
vehicle:
.PressQorKon the remote key. See
Remote Keyless Entry (RKE) System
Operation 08.
.Use the mechanical key in the
driver door.
To lock or unlock the doors from inside the
vehicle:

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
18 Keys, Doors, and Windows
To open a rear door when the safety lock
is on:1. Unlock the door by activating the inside handle, by pressing the power door
unlock switch, or by using the
remote key.
2. Open the door from the outside.
When the safety lock is enabled, adults and
older children will not be able to open the
rear door from the inside. Cancel the safety
locks to enable the doors to open from the
inside.
To cancel the safety lock: 1. Unlock the door and open it from the outside.
2. Move the lever up to unlock. Do the same for the other door.
Doors
Liftgate
{Warning
Exhaust gases can enter the vehicle if it
is driven with the liftgate or trunk/hatch
open, or with any objects that pass
(Continued)
Warning (Continued)
through the seal between the body and
the trunk/hatch or liftgate. Engine
exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can
cause unconsciousness and even death.
If the vehicle must be driven with the
liftgate or trunk/hatch open:
.Close all of the windows.
.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
and set the fan speed to the highest
setting. See“Climate Control Systems”
in the Index.
.If the vehicle is equipped with a
power liftgate, disable the power
liftgate function.
See Engine Exhaust 0231.
Caution
To avoid damage to the liftgate or
liftgate glass, make sure the area above
and behind the liftgate is clear before
opening it.
Manual Liftgate
To open the liftgate, pressKon the power
door lock switch or press
Kon the remote
key twice to unlock all doors. Press the
touch pad (1) on the underside of the
liftgate handle and lift up.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Keys, Doors, and Windows 25
Power Assist Steps
{Warning
To avoid personal injury or property
damage, before entering or exiting the
vehicle, be sure the power assist step is
fully extended. Do not step on the power
assist step while it is moving. Never place
hands or other body parts between the
extended power assist step and the
vehicle.
If equipped, the power assist steps will
deploy when the door is opened and
automatically retract three seconds after the
door is closed. The power assist steps will
retract immediately if the vehicle starts
moving.
Disable the power assist steps before jacking
or placing any object under the vehicle. Too
much ice buildup may prevent deployment
of the power assist steps. Check the step
position before exiting the vehicle. If this
happens, disable the power assist steps,
clear the ice, then enable the assist steps
and confirm normal function prior to use. Keep hands, children, pets, objects, and
clothing clear of the power assist steps
when in motion. The steps will reverse
direction if they encounter an obstruction
when opening or closing. Remove the
obstruction, then open and close the door
on the same side to complete the motion of
the assist steps. If the obstruction is not
cleared, the assist steps remain extended
while driving.
To extend or retract both power assist steps
for cleaning, see
Vehicle Personalization
0 126.
Enable/Disable
To enable or disable the power assist steps,
see Vehicle Personalization 0126.
Vehicle Security
This vehicle has theft-deterrent features;
however, they do not make the vehicle
impossible to steal.
Vehicle Alarm System
The indicator light, on the driver door near
the window, indicates the status of the
system. See Power Door Locks 016
Arming the Alarm System
1. Turn off the vehicle.
2. Lock the vehicle in one of three ways:
.Use the remote key.
.Use the Keyless Access system.
.With a door open, pressQon the
interior of the door.
3. After 30 seconds the alarm system will arm, and the indicator light will begin to
slowly flash. Pressing
Qon the remote

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Seats and Restraints 39
To fold the head restraint, press the button
on the side of the head restraint.
The head restraint will fold forward
automatically.When an occupant or child restraint is in the
seat, always return the head restraint to the
full upright position. Push the head restraint
up and rearward until it locks into place.
Push and pull on the head restraint to make
sure that it is locked.
Third Row Seats
The vehicle’s third row seats have head
restraints in the outboard seating positions
that cannot be adjusted up or down.
The third row outboard head restraints are
not removable.
The third row outboard head restraints are
designed to be folded.
When folding the third row seatbacks down,
the head restraint will automatically fold
out of the way as the seat is folded down.
The head restraint can be folded forward to
allow for better visibility when the rear seat
is unoccupied.
To fold the head restraint, press the button
on the side of the head restraint.
The head restraint will fold forward
automatically.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
40 Seats and Restraints
When an occupant or child restraint is in the
seat, always return the head restraint to the
full upright position. Push the head restraint
up and rearward until it locks into place.
Push and pull on the head restraint to make
sure that it is locked.
Front Seats
Power Seat Adjustment
{Warning
You can lose control of the vehicle if you
try to adjust a driver seat while the
vehicle is moving. Adjust the driver seat
only when the vehicle is not moving.
{Warning
The power seats will work with the
ignition off. Children could operate the
power seats and be injured. Never leave
children alone in the vehicle.
To adjust the seat:
.Move the seat forward or rearward by
sliding the control forward or rearward.
.If equipped, raise or lower the front part
of the seat cushion by moving the front
of the control up or down.
.Raise or lower the seat by moving the
rear of the control up or down.
Lumbar Adjustment
.Press and hold the front or rear of the
control to increase or decrease lumbar
support.
.If equipped, press and hold the top or
bottom of the control to raise or lower
lumbar support.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
72 Seats and Restraints
{Warning
Never allow a child to wear the seat belt
shoulder belt under both arms or behind
their back. A child can be seriously
injured by not wearing the lap-shoulder
belt properly. In a crash, the child would
not be restrained by the shoulder belt.
The child could move too far forward
increasing the chance of head and neck
injury. The child might also slide under
the lap belt. The belt force would then be
applied right on the abdomen. That could
cause serious or fatal injuries. The
shoulder belt should go over the shoulder
and across the chest.
Infants and Young Children
Everyone in a vehicle needs protection! This
includes infants and all other children.
Neither the distance traveled nor the age
and size of the traveler changes the need,
for everyone, to use safety restraints. In
fact, the law in every state in the United
States and in every Canadian province says
children up to some age must be restrained
while in a vehicle.
{Warning
Children can be seriously injured or
strangled if a shoulder belt is wrapped
around their neck. The shoulder belt can(Continued)
Warning (Continued)
tighten but cannot be loosened if it is
locked. The shoulder belt locks when it is
pulled all the way out of the retractor.
It unlocks when the shoulder belt is
allowed to go all the way back into the
retractor, but it cannot do this if it is
wrapped around a child’s neck. If the
shoulder belt is locked and tightened
around a child’s neck, the only way to
loosen the belt is to cut it.
Never leave children unattended in a
vehicle and never allow children to play
with the seat belts.
Every time infants and young children ride
in vehicles, they should have the protection
provided by appropriate child restraints.
Neither the vehicle’s seat belt system nor its
airbag system is designed for them.
Children who are not restrained properly can
strike other people, or can be thrown out of
the vehicle.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
82 Seats and Restraints
{Warning
Children can be seriously injured or
strangled if a shoulder belt is wrapped
around their neck. The shoulder belt can
tighten but cannot be loosened if it is
locked. The shoulder belt locks when it is
pulled all the way out of the retractor.
It unlocks when the shoulder belt is
allowed to go all the way back into the
retractor, but it cannot do this if it is
wrapped around a child’s neck. If the
shoulder belt is locked and tightened
around a child’s neck, the only way to
loosen the belt is to cut it.
Buckle any unused seat belts behind the
child restraint so children cannot reach
them. Pull the shoulder belt all the way
out of the retractor to set the lock, and
tighten the belt behind the child restraint
after the child restraint has been
installed.
Caution
Do not let the LATCH attachments rub
against the vehicle’s seat belts. This may
damage these parts. If necessary, move
buckled seat belts to avoid rubbing the
LATCH attachments.
Do not fold the rear seatback when the
seat is occupied. Do not fold the empty
rear seat with a seat belt buckled. This
could damage the seat belt or the seat.
Unbuckle and return the seat belt to its
stowed position, before folding the seat.
The vehicle is equipped with a front center
airbag in the inboard side of the driver seat.
Even with a front center airbag, a child
restraint can be installed in any second row
seating position.
If you need to secure more than one child
restraint in the rear seat, see Where to Put
the Restraint 076.
1. Attach and tighten the lower attachments to the lower anchors. If the
child restraint does not have lower
attachments or the desired seating
position does not have lower anchors,
secure the child restraint with the seat
belt and top tether when recommended by the child restraint manufacturer. Refer
to your child restraint manufacturer
instructions and the instructions in this
manual.
1.1. Find the lower anchors for the
desired seating position.
1.2. Put the child restraint on the seat.
1.3. Attach and tighten the lower attachments on the child restraint
to the lower anchors.
2. If the child restraint manufacturer recommends that the top tether be
attached, attach and tighten the top
tether to the top tether anchor. Refer to
the child restraint instructions and the
following steps:
2.1. Find the top tether anchor.
2.2. Route, attach, and tighten the top tether according to your child
restraint instructions and the
following instructions: