2020 GMC SIERRA alarm

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Driving and Operating 321
Trailer Detection Alert
The Trailer Detection Alert setting
will be on by default. Turn it off to
disable the Trailer Detection pop-up
from displaying when a trailer is
connected. The Guest Trailer Profile
will become the active Trailer
Profile, unless another Trailer Profile
is selected manually through the
Trailering App. If this setting is
disabled while a Custom Trailer
Profile is active, that Trailer Profile
will remain the active profile until the
trailer is disconnected.
Maintenance Alerts
Touch Maintenance Alerts to view
the Maintenance Alerts 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.
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 or
connected service plan and thesmartphone 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 0226.
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
OnStar 479
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. Press
Qto 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.
Reactivation for Subsequent
Owners
PressQand follow the prompts to
speak to an Advisor as soon as
possible. The Advisor will update
vehicle records and explain OnStar
or connected service options.
How OnStar Service Works
Automatic Crash Response,
Emergency Services, Crisis Assist,
Stolen Vehicle Assistance, Remote
Services, and Roadside Assistance
are available on most vehicles. Not
all OnStar services are available
everywhere or on all vehicles. For
more information, a full description
of OnStar services, system
limitations, and OnStar User Terms,
Privacy Statement, and Software
Terms:
. Call 1-888-4ONSTAR
(1-888-466-7827).
. See www.onstar.com (U.S.).
. See www.onstar.ca (Canada).
. Call TTY 1-877-248-2080.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 4/4/19
488 Index
IndexA
Accessories andModifications . . . . . . . . . . . . . . . . . . 329
Accessory Power . . . . . . . . . . . . . . . 217
Active Fuel Management . . . . . . . 219
Adaptive Cruise Control . . . . . . . . 245
Add-On Electrical Equipment . . . 322
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . . . 323
Additional Information
OnStar . . . . . . . . . . . . . . . . . . . . . . . 479
Additional Maintenance and Care . . . . . . . . . . . . . . . . . . . . . . 450
Adjustments
Lumbar, Front Seats . . . . . . . . . . . . 57
Air Cleaner/Filter, Engine . . . . . . . 344
Air Conditioning . . . . . . . . . . . 177, 179
Air Filter Life System . . . . . . . . . . . . . . . . . . . 343
Air Filter, Passenger Compartment . . . . . . . . . . . . . . . . . 183
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 182
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . 84
How Does an Airbag
Restrain? . . . . . . . . . . . . . . . . . . . . . 77
Passenger Sensing System . . . . 78 Airbag System (cont'd)
What Makes an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 76
What Will You See after an
Airbag Inflates? . . . . . . . . . . . . . . . 77
When Should an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 76
Where Are the Airbags? . . . . . . . . 74
Airbags
Adding Equipment to theVehicle . . . . . . . . . . . . . . . . . . . . . . . . 83
Passenger Status Indicator . . . 137
Readiness Light . . . . . . . . . . . . . . 136
Servicing Airbag-Equipped Vehicles . . . . . . . . . . . . . . . . . . . . . . . 83
System Check . . . . . . . . . . . . . . . . . . 72
Alarm Vehicle Security . . . . . . . . . . . . . . . . 37
Alert Lane Change . . . . . . . . . . . . . . . . . 274
Side Blind Zone (SBZA) . . . . . . 274
All-Season Tires . . . . . . . . . . . . . . . . 379
All-Terrain Tires . . . . . . . . . . . . . . . . . 381
Antilock Brake System (ABS) . . . 232 Warning Light . . . . . . . . . . . . . . . . . 141
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . 429
Interior . . . . . . . . . . . . . . . . . . . . . . . . 435

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 4/4/19
Index 497
Roadside AssistanceProgram . . . . . . . . . . . . . . . . . . . . . . . 467
Roof Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . 51
Rotation, Tires . . . . . . . . . . . . . . . . . . 396
Routing, Engine Drive Belt . . . . . . 462
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . . . . 220
S
Safety Defects ReportingCanadian Government . . . . . . . . 473
General Motors . . . . . . . . . . . . . . . 474
U.S. Government . . . . . . . . . . . . . 473
Safety Locks . . . . . . . . . . . . . . . . . . . . . 27
Safety System Check . . . . . . . . . . . . 71
Scheduling Appointments . . . . . . . 468
Seat Belts . . . . . . . . . . . . . . . . . . . . . . . 65 Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Extender . . . . . . . . . . . . . . . . . . . . . . . . 71
How to Wear Seat BeltsProperly . . . . . . . . . . . . . . . . . . . . . . . 66
Lap-Shoulder Belt . . . . . . . . . . . . . . 68
Reminders . . . . . . . . . . . . . . . . . . . . 136
Replacing after a Crash . . . . . . . . 72
Use During Pregnancy . . . . . . . . . . 70
Seats Adjustment, Front . . . . . . . . . . . . . . . 55 Seats (cont'd)
Center Seat . . . . . . . . . . . . . . . . . . . . 56
Head Restraints . . . . . . . . . . . . . . . . 54
Heated and Ventilated Front . . . . 61
Heated, Rear . . . . . . . . . . . . . . . . . . . 64
Lumbar Adjustment, Front . . . . . . 57
Memory . . . . . . . . . . . . . . . . . . . . . . . . . 59
Power Adjustment, Front . . . . . . . 56
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Reclining Seatbacks . . . . . . . . . . . . 57
Underseat Storage . . . . . . . . . . . .114
Securing Child Restraints . . . . . . . . . . .105, 108, 109
Security
Light . . . . . . . . . . . . . . . . . . . . . . . . . . 147
OnStar . . . . . . . . . . . . . . . . . . . . . . . 479
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . 37
Vehicle Alarm . . . . . . . . . . . . . . . . . . . 37
Service . . . . . . . . . . . . . . . . . . . . . . . . . 184 Accessories andModifications . . . . . . . . . . . . . . . . 329
Climate Control System . . . . . . . 177
Doing Your Own Work . . . . . . . . 330
Maintenance Records . . . . . . . . 457
Maintenance, General Information . . . . . . . . . . . . . . . . . . 440
Parts Identification . . . . . . . . . . . . 458
Scheduling Appointments . . . . . 468 Service Electric Parking
Brake Light . . . . . . . . . . . . . . . . . . . . 141
Services Special Application . . . . . . . . . . . 449
Servicing the Airbag . . . . . . . . . . . . . 83
Shift Lock Control Function Check, Automatic
Transmission . . . . . . . . . . . . . . . . . . 363
Shifting Into Park . . . . . . . . . . . . . . . . . . . . . . 217
Out of Park . . . . . . . . . . . . . . . . . . . 218
Side Blind Zone Alert (SBZA) . . . 274
Signals, Turn and Lane-Change . . . . . . . . . . . . . . . . . 170
Snow Plow . . . . . . . . . . . . . . . . . . . . . 323
Special Application Services . . . . 449
Specifications and Capacities . . . . . . . . . . . . . . . . . . . . . 459
Speedometer . . . . . . . . . . . . . . . . . . . 131
Start Assist, Hill . . . . . . . . . . . . . . . . . 235
Start Vehicle, Remote . . . . . . . . . . . 24
Starter Switch Check . . . . . . . . . . . 363
Starting the Engine . . . . . . . . . . . . . 212
Steering . . . . . . . . . . . . . . . . . . . . . . . . 188 Fluid, Power . . . . . . . . . . . . . . . . . . 354
Heated Wheel . . . . . . . . . . . . . . . . 120
Wheel Adjustment . . . . . . . . . . . . .119
Wheel Controls . . . . . . . . . . . . . . . 120

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 4/4/19
Index 499
Traction Control/ElectronicStability Control . . . . . . . . . . . . . . . 235
Trailer Sway Control (TSC) . . . . . . . . . . 308
Tow Mirrors . . . . . . . . . . . . . . . . . . . . . 41
Towing . . . . . . . . . . . . . . . . . . . . . . . . 292
Trailer Towing
App . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Trailering App . . . . . . . . . . . . . . . . . . 310
Transfer Case . . . . . . . . . . . . . . . . . . 227
Transmission Automatic . . . . . . . . . . . . . . . . . . . . . 221
Fluid, Automatic . . . . . . . . . . . . . . 343
Transportation Program, Courtesy . . . . . . . . . . . . . . . . . . . . . . 469
Trip Odometer . . . . . . . . . . . . . . . . . . 132
Truck-Camper Loading
Information . . . . . . . . . . . . . . . . . . . . 206
Turn and Lane-Change Signals . . . . . . . . . . . . . . . . . . . . . . . . 170
Turn Signal
Bulb Replacement . . . . . . . . . . . . 368U
Underseat Storage . . . . . . . . . . . . . 114
Uniform Tire Quality Grading . . . 401
Universal Remote System . . . . . . 161Operation . . . . . . . . . . . . . . . . . . . . . 164
Programming . . . . . . . . . . . . . . . . . 161
Using This Manual . . . . . . . . . . . . . . . . 2
V
Vehicle Alarm System . . . . . . . . . . . . . . . . . . 37
Canadian Owners . . . . . . . . . . . . . . . 2
Control . . . . . . . . . . . . . . . . . . . . . . . 188
Identification Number (VIN) . . . 458
Load Limits . . . . . . . . . . . . . . . . . . . 200
Messages . . . . . . . . . . . . . . . . . . . . 156
Personalization . . . . . . . . . . . . . . . 157
Remote Start . . . . . . . . . . . . . . . . . . . 24
Security . . . . . . . . . . . . . . . . . . . . . . . . 37
Speed Messages . . . . . . . . . . . . . 156
Towing . . . . . . . . . . . . . . . . . . . . . . . . 424
Vehicle Ahead Indicator . . . . . . . . 143
Vehicle Care Tire Pressure . . . . . . . . . . . . . . . . . 387
Vehicle Data Recording and Privacy . . . . . . . . . . . . . . . . . . . . . . . . 474
Vehicle Security Steering Column Lock . . . . . . . . . . 38 Ventilation, Air . . . . . . . . . . . . . . . . . . 182
Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Voltmeter Gauge . . . . . . . . . . . . . . . 135
W
Warning
Brake System Light . . . . . . . . . . . 140
Caution and Danger . . . . . . . . . . . . . 3
Lane Departure (LDW) . . . . . . . 276
Warning Lights, Gauges, and Indicators . . . . . . . . . . . . . . . . . . . . . 126
Warnings
Hazard Flashers . . . . . . . . . . . . . . 169
Washer Fluid . . . . . . . . . . . . . . . . . . . 354
Wheels Alignment and Tire Balance . . 403
Different Size . . . . . . . . . . . . . . . . . 401
Replacement . . . . . . . . . . . . . . . . . 403
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 398
Where to Put the Restraint . . . . . . 91
Windows . . . . . . . . . . . . . . . . . . . . . . . . 48
Manual . . . . . . . . . . . . . . . . . . . . . . . . . 49
Power . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Windshield
Replacement . . . . . . . . . . . . . . . . . 365
Wiper/Washer . . . . . . . . . . . . . . . . 120