2021 GMC YUKON change key battery

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
140 Lighting
With Sunroof
Press the lens on each reading lamp to turn
it on or off.
Lighting Features
Entry Lighting
Some exterior lamps turn on briefly at
night, or in areas with limited lighting,
when
Kis pressed on the remote key. After about 30 seconds the exterior lamps turn off
when any door is opened, the unlock button
on the remote key is pressed, or when the
ignition is switched off. All interior lights
turn on and then the dome and remaining
interior lamps dim to off after 20 seconds.
Entry lighting feature for exterior lighting
can be changed by Vehicle Locator Lights.
See Vehicle Locator Lights under
Vehicle
Personalization 0126.
Exit Lighting
Some exterior lamps come on at night, or in
areas with limited lighting, when the driver
door is opened after the ignition is turned
off. The dome lamp comes on after the
ignition is turned off. The exterior lamps and
dome lamp remain on after the door is
closed for a set amount of time, then
automatically turn off.
The exterior lamps turn off immediately by
turning the exterior lamp control off.
The exit lighting for exterior lights can be
changed. See Vehicle Personalization 0126.
Battery Load Management
The vehicle has Electric Power Management
(EPM), which estimates the battery's
temperature and state of charge. It then
adjusts the voltage for best performance
and extended life of the battery.
When the battery's state of charge is low,
the voltage is raised slightly to quickly bring
the charge back up. When the state of
charge is high, the voltage is lowered
slightly to prevent overcharging. The
voltmeter gauge or the voltage display on
the Driver Information Center (DIC),
if equipped, may show the voltage moving
up or down. This is normal. If there is a
problem, an alert will be displayed.
The battery can be discharged at idle if the
electrical loads are very high. This is true for
all vehicles. This is because the generator
(alternator) may not be spinning fast
enough at idle to produce all the power that
is needed for very high electrical loads.
A high electrical load occurs when several of
the following are on, such as: headlamps,
high beams, fog lamps, rear window
defogger, climate control fan at high speed,

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13690468) - 2021 - crc - 8/14/20
228 Driving and Operating
Service Mode
This power mode is available for service and
diagnostics, and to verify the proper
operation of the malfunction indicator lamp
as may be required for emission inspection
purposes. With the vehicle off, and the
brake pedal not applied, pressing and
holding the button for more than
five seconds will place the vehicle in Service
Mode. The instruments and audio systems
will operate as they do when the ignition is
on, but the vehicle will not be able to be
driven. The engine will not start in Service
Mode. Press the button again to turn the
ignition off.
Starting the Engine
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
Caution
If you add electrical parts or accessories,
you could change the way the engine
operates. Any resulting damage would
not be covered by the vehicle warranty.
SeeAdd-On Electrical Equipment 0306. Shift the vehicle into P (Park) or N (Neutral).
To restart the engine when the vehicle is
already moving, use N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could
damage the transmission. Shift to P (Park)
only when the vehicle is stopped.
Starting Procedure
1. The remote key 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.
Operate the engine and transmission
gently to allow the oil to warm up and
lubricate all moving parts.
When the low fuel warning light is on
and the FUEL LEVEL LOW message is
displayed in the Driver Information
Center (DIC), press the ENGINE START/
STOP position to continue engine
cranking.
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 while
pressing 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 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.

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.

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