2021 GMC YUKON alarm

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 9
Q:Press to lock all doors.
If enabled, the turn signal lamps flash once
on the second press to indicate locking has
occurred. If enabled, the horn chirps when
Qis pressed again within three seconds. See
Vehicle Personalization 0126.
Pressing
Qarms the alarm system. See
Vehicle Alarm System 025.
If equipped with auto mirror folding,
pressing and holding
Qfor one second will
fold the mirrors, if enabled. See Vehicle
Personalization 0126.
K:Press once to unlock only the driver
door. If
Kis pressed again within
three seconds, all remaining doors unlock.
The interior lamps may come on and stay
on for 20 seconds or until the ignition is
turned on.
If enabled, the turn signal lamps flash twice
to indicate unlocking has occurred.
If enabled, the exterior lamps may turn on.
See Vehicle Personalization 0126.
Pressing
Kon the remote key disarms the
alarm system. See Vehicle Alarm System
0 25. If equipped with auto mirror folding,
pressing and holding
Kfor one second will
unfold the mirrors, if enabled. See Vehicle
Personalization 0126.
Press and hold
Kuntil the windows fully
open, if remote window operation is
enabled. See Vehicle Personalization 0126.
b:Press twice to open or close the
liftgate. Press once to stop the liftgate from
moving.
c: Press twice to open the liftglass.
7:Press and release to initiate vehicle
locate. The turn signal lamps flash and the
horn sounds three times.
Press and hold
7for more than
three seconds to activate the panic alarm.
The turn signal lamps flash and the horn
sounds repeatedly for 30 seconds. The alarm
turns off when the ignition is turned on or
7is pressed again. The ignition must be off
for the panic alarm to work.
/: To remote start the vehicle, double
press
/from outside the vehicle using the
remote key. The vehicle cannot be started if
a remote key is left inside the vehicle. See
Remote Vehicle Start 014.
Keyless Access Operation
The Keyless Access system allows for doors
and the liftgate to be accessed without
removing the remote key from your pocket,
purse, briefcase, etc. The remote key must
be within 1 m (3 ft) of the liftgate or door
being opened. If the vehicle has this feature,
there will be a button on the outside door
handles.
Keyless Access can be programmed to
unlock all doors on the first lock/unlock
press from the driver door. See Vehicle
Personalization 0126.
If equipped with memory seats, remote keys
1 and 2 are linked to seating positions of
memory 1 or 2. See Memory Seats041.
Keyless Unlocking/Locking from the
Driver Door
When the doors are locked and the remote
key is within 1 m (3 ft) of the door handle,
pressing the lock/unlock button on the
driver door handle will unlock the driver
door. If the lock/unlock button is pressed
again within five seconds, all passenger
doors and the liftgate will unlock.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
10 Keys, Doors, and Windows
Driver Side Shown, Passenger Side Similar
Pressing the lock/unlock button will cause
all doors to lock if any of the following
occur:
.It has been more than five seconds since
the first lock/unlock button press.
.Two lock/unlock button presses were
used to unlock all doors.
.Any vehicle door has been opened and all
doors are now closed.
Keyless Unlocking/Locking from the
Passenger Doors
When the doors are locked and the remote
key is within 1 m (3 ft) of the door handle,
pressing the lock/unlock button on a
passenger door handle will unlock all doors. Pressing the lock/unlock button will cause
all doors to lock if any of the following
occur:
.The lock/unlock button was used to
unlock all doors.
.Any vehicle door has been opened and all
doors are now closed.
Disable/Enable Keyless Unlocking of Exterior
Door Handles and Liftgate
If equipped, keyless unlocking of the exterior
door handles and liftgate can be disabled
and enabled.
Disabling Keyless Unlocking:
With the vehicle off, press and hold
Qand
Kon the remote key at the same time for
approximately three seconds. The turn signal
lamps will flash four times quickly to
indicate access is disabled. Using any
exterior handle to unlock the doors or open
the liftgate will cause the turn signal lamps
to flash four times quickly, indicating access
is disabled. If disabled, disarm the alarm
system before starting the vehicle.
Disabling Keyless Unlocking may also be
configured under Vehicle Personalization
0 126. Enabling Keyless Unlocking:
With the vehicle off, press and hold
Qand
Kon the remote key at the same time for
approximately three seconds. The turn signal
lamps will flash twice quickly to indicate
access is enabled.
Enabling Keyless Unlocking may also be
configured under Vehicle Personalization
0 126.
Passive Locking
The Keyless Access system will lock the
vehicle several seconds after all doors are
closed, if the vehicle is off and at least one
remote key has been removed from the
interior, or none remain in the interior.
If other electronic devices interfere with the
remote key signal, the vehicle may not
detect the remote key inside the vehicle.
If passive locking is enabled, the doors may
lock with the remote key inside the vehicle.
Do not leave the remote key in an
unattended vehicle.
To customize the doors to automatically lock
when exiting the vehicle, see “Remote Lock,
Unlock, Start” underVehicle Personalization
0 126.

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
26 Keys, Doors, and Windows
key a second time will bypass the
30-second delay and immediately arm
the alarm system.
The vehicle alarm system will not arm if the
doors are locked with the mechanical key.
If the driver door is opened without first
unlocking with the remote key, the horn will
chirp and the lights will flash to indicate
pre-alarm. If the vehicle is not started,
or the door is not unlocked by pressing
K
on the remote key during the 10-second
pre-alarm, the alarm will be activated.
The alarm will also be activated if a
passenger door, the liftgate, or the hood is
opened without first disarming the system.
When the alarm is activated, the turn
signals flash and the horn sounds for about
30 seconds. The alarm system will then
re-arm to monitor for the next unauthorized
event.
Disarming the Alarm System
To disarm the alarm system or turn off the
alarm if it has been activated:
.PressKon the remote key.
.Unlock the vehicle using the Keyless
Access system.
.Start the vehicle. To avoid setting off the alarm by accident:
.Lock the vehicle after all occupants have
exited.
.Always unlock a door with the remote
key, or use the Keyless Access system.
Unlocking the driver door with the
mechanical key will not disarm the
system or turn off the alarm.
How to Detect a Tamper Condition
IfKis pressed on the remote key and the
horn chirps three times, an alarm occurred
previously while the alarm system was
armed.
If the alarm has been activated, a message
will appear on the DIC.
Power Sounder, Inclination Sensor, and
Intrusion Sensor
In addition to the standard theft-deterrent
system features, this system may also have
a power sounder, inclination sensor, and
intrusion sensor.
The power sounder provides an audible
alarm which is distinct from the vehicle’s
horn. It has its own power source, and can
sound an alarm if the vehicle’s battery is
compromised. The inclination sensor can set off the alarm
if it senses movement of the vehicle, such
as a change in vehicle orientation.
The intrusion sensor monitors the vehicle
interior, and can activate the alarm if it
senses unauthorized entry into the vehicle’s
interior. Do not allow passengers or pets to
remain in the vehicle when the intrusion
sensor is activated.
Before arming the theft-deterrent system
and activating the intrusion sensor:
.Make sure all doors and windows are
completely closed.
.Secure any loose items such as a
sunshades.
.Make sure there are no obstructions
blocking the sensors in the front overhead
console.
.Close DVD screens before leaving the
vehicle.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
Keys, Doors, and Windows 27
Intrusion and Inclination Sensors Disable
Switch
It is recommended that the intrusion and
inclination sensors be deactivated if pets are
left in the vehicle or the vehicle is being
transported.
With the vehicle off, press
oin the front
overhead console to turn off the feature.
The indicator light will come on
momentarily, indicating that these sensors
have been disabled until the next time the
alarm system is armed.
Steering Column Lock
If equipped, the steering column lock is a
theft-deterrent device. This feature locks the
steering column when the vehicle is turned
off and the driver door is opened, or when
the driver door is opened and then the
vehicle is turned off. The steering column
unlocks when the vehicle is turned on.
The Driver Information Center (DIC) may
display one of these messages:
.A message to service the steering column
lock indicates that an issue has been
detected with the column lock feature
and the vehicle should be serviced.
.A message that the steering column is
locked indicates that the engine is
running, but the steering column is still
locked. It is normal for the column to be
locked during a remote start, but the
column should unlock after the brake
pedal is pressed and the vehicle is started.
No message will display during a remote
start.
.A message that the steering wheel must
be turned and the vehicle must be started
again indicates that the column lock
mechanism is bound, the column locking
device was unable to unlock the steering column, and the vehicle did not start.
If this happens, immediately turn the
steering wheel from side to side to
unbind the column lock. If this does not
unlock the steering column, turn the
vehicle off and open the driver door to
reset the system. Then turn the vehicle
on and immediately turn the steering
wheel side to side for about 15 seconds.
In some cases, it may take significant
force to unbind the column.
To keep the steering column from binding,
straighten the front wheels before turning
off the vehicle.
Immobilizer
See Radio Frequency Statement 0407.
Immobilizer Operation
This vehicle has a passive theft-deterrent
system.
The system does not have to be manually
armed or disarmed.
The vehicle is automatically immobilized
when the vehicle is turned off.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
306 Driving and Operating
The setting will be on by default for each
profile. All Maintenance Alerts for that active
Trailer Profile will be received.
Turn a setting off to not receive any of the
Maintenance Alerts when that Trailer Profile
is active.
Theft Alert
A theft alert can be set if a trailer is
connected and the alert is enabled. When
the trailer is disconnected and the vehicle is
off, an alarm will sound.
Touch Theft Alert in Settings to view the
Theft Alert settings page. These alerts are
based on the Trailer Profile, so the settings
for each Trailer Profile must be turned on or
off. Touch a profile to view more
information or adjust the setting for that
profile.
This setting will be off by default for each
Trailer Profile, including the Guest Trailer
Profile.
A smartphone will receive a notification that
the trailer related to the selected Trailer
Profile is disconnected from the vehicle,
if the setting is on for the active Trailer
Profile, the vehicle has an OnStar orconnected service plan and the smartphone
number has been added to the account for
this notification.
If the setting is turned off for a given Trailer
Profile, the smartphone will not receive this
security notification even if the Trailer
Profile is active.Tow/Haul Mode Reminder
This is a reminder to turn on the Tow/Haul
Mode when towing a trailer. See
Tow/Haul
Mode 0235.
Touch Tow/Haul Mode Reminder in Settings
to view the Tow/Haul Mode Reminder
settings page. These alerts are based on the
Trailer Profile, so the settings for each
Trailer Profile must be turned on or off.
Touch a profile to view more information or
to adjust the setting for that profile.
This setting will default to OFF for each
Trailer Profile, including the Guest Trailer
Profile.
If Tow/Haul Mode is off and this setting is
on for a Trailer Profile, each time the
ignition is turned on a reminder will appear
to turn on Tow/Haul Mode when the Trailer
Profile is active. If Tow/Haul Mode is on and this setting is
on for a Trailer Profile, the reminder will not
appear when the Trailer Profile is active.
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. See
Malfunction
Indicator Lamp (Check Engine Light) 0111.
A device connected to the DLC —such as
an aftermarket fleet or driver-behavior
tracking device —may interfere with
vehicle systems. This could affect vehicle
operation and cause a crash. Such devices
may also access information stored in the
vehicle’s systems.
Caution
Some electrical equipment can damage
the vehicle or cause components to not
work and would not be covered by the
vehicle warranty. Always check with your
dealer before adding electrical equipment.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
OnStar 411
.Receive a Diagnostic check of the vehicle's
key operating systems.
.Receive Roadside Assistance.
.Manage Wi-Fi Settings, if equipped.
Press
>to get a priority connection to an
OnStar Advisor available 24/7 to:
.Get help for an emergency.
.Be a Good Samaritan or respond to an
AMBER Alert.
.Get assistance in severe weather or other
crisis situations and find evacuation
routes.
OnStar Services
Emergency
Emergency Services require an active safety
and security plan. With Automatic Crash
Response, built-in sensors can automatically
alert a specially trained OnStar Advisor who
is immediately connected in to the vehicle
to help.
Press
>for a priority connection to an
OnStar Advisor who can contact emergency
service providers, direct them to your exact
location, and relay important information. With OnStar Crisis Assist, specially trained
Advisors are available 24 hours a day, 7 days
a week, to provide a central point of
contact, assistance, and information during a
crisis.
With Roadside Assistance, Advisors can
locate a nearby service provider to help with
a flat tire, a battery jump, or an empty
gas tank.
Security
If equipped, OnStar provides these services:
.With Stolen Vehicle Assistance, OnStar
Advisors can use GPS to pinpoint the
vehicle and help authorities quickly
recover it.
.With Remote Ignition Block, if equipped,
OnStar can block the engine from being
restarted.
.With Stolen Vehicle Slowdown,
if equipped, OnStar can work with law
enforcement to gradually slow the
vehicle down.
Theft Alarm Notification
If equipped, if the doors are locked and the
vehicle alarm sounds, a notification by text,
e-mail, or phone call will be sent. If the
vehicle is stolen, an OnStar Advisor can work
with authorities to recover the vehicle.
OnStar Additional
Information
In-Vehicle Audio Messages
Audio messages may play important
information at the following times:
.Prior to vehicle purchase. PressQto set
up an account.
.After change in ownership and at
90 days.
Transferring Service
PressQto request account transfer
eligibility information. The Advisor can
cancel or change account information.
Selling/Transferring the Vehicle
Call 1-888-4ONSTAR (1-888-466-7827)
immediately to terminate your OnStar or
connected services if the vehicle is disposed
of, sold, transferred, or if the lease ends.