2023 GMC SIERRA horn

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
388 Service and Maintenance
Systems, Fluids, and Visible Leak
Inspection
.Engine oil
.Transmission
.Drive axle
.Transfer case
.Engine cooling system
.Power steering, if equipped
.Fuel system
.Windshield washer fluid
Tire Inspection
.Tire pressure, tread depth, and wear
.Rotation, if applicable
.Alignment check, optional
.Reset tire pressure monitor
.Check tire sealant expiration date,
if equipped
.Check spare tire, if equipped
Brakes
.Check brake system
Visible and Functional Inspections
.Seat belt components
.Exhaust system
.Accelerator pedal
.Passenger compartment air filter,
if equipped
.Engine air filter
.Hoses
.Belts
.Shocks and struts
.Steering components
.Axle boots or driveshaft and u-joints
.Compartment lift struts, if equipped
.Floor mats secured, no interference with
pedals
.Horn
.Ignition lock, if equipped
.Starter switch
.Evaporative control system
Lubricate
.Chassis components
Special Application Services
.Vehicles with Dual Wheels: Check dual
wheel nut torque at 160, 1 600, and
10 000 km (100, 1,000, and 6,000 mi) of
driving. Repeat this service whenever a
tire/wheel is serviced or removed.
.Severe Commercial Use Vehicles Only:
Lubricate chassis components every oil
change.
.Have underbody flushing service
performed. See “Underbody Maintenance”
in Exterior Care 0374.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
414 Connected Services
Ensuring Security
.Change the default passwords for the
Wi-Fi hotspot and myGMC mobile
application. Make these passwords
different from each other and use a
combination of letters and numbers to
increase the security.
.Change the default name of the SSID
(Service Set Identifier). This is your
network’s name that is visible to other
wireless devices. Choose a unique name
and avoid family names or vehicle
descriptions.
Wi-Fi Hotspot (If Equipped)
The vehicle may have a built-in Wi-Fi
hotspot that provides access to the Internet
and web content at 4G LTE speed. Up to
seven mobile devices can be connected.
A data plan is required. Use the in-vehicle
controls only when it is safe to do so. 1. To retrieve Wi-Fi hotspot information, press
=to open the OnStar app on the
infotainment display, then select Wi-Fi
Hotspot. On some vehicles, touch Wi-Fi
or Wi-Fi Settings on the screen.
2. The Wi-Fi settings will display the Wi-Fi hotspot name (SSID), password, and on
some vehicles, the connection type (no Internet connection, 3G, 4G, 4G LTE), and
signal quality (poor, good, excellent). The
LTE icon shows connection to Wi-Fi. It is
possible that the icon may not illuminate
even though the vehicle has an active
connection.
3. To change the SSID or password, press
Qor call 1-888-4ONSTAR to connect
with an Advisor. On some vehicles, the
SSID and password can be changed in
the Wi-Fi Hotspot menu.
After initial set-up, your vehicle’s Wi-Fi
hotspot will connect automatically to your
mobile devices. Manage data usage by
turning Wi-Fi on or off on your mobile
device, using the myGMC mobile app, or by
contacting an OnStar Advisor. On some
vehicles, Wi-Fi can also be managed from
the Wi-Fi Hotspot menu.
MyGMC Mobile App (If Available)
Download the myGMC mobile app to
compatible Apple and Android smartphones.
GMC users can access the following services
from a smartphone:
.Remotely start/stop the vehicle,
if factory-equipped.
.Lock/unlock doors, if equipped with
automatic locks.
.Activate the horn and lamps.
.Check the vehicle’s fuel level, oil life,
or tire pressure, if factory-equipped with
the Tire Pressure Monitor System.
.Send destinations to the vehicle.
.Locate the vehicle on a map
(U.S. market only).
.Turn the vehicle's Wi-Fi hotspot on/off,
manage settings, and monitor data
consumption, if equipped.
.Locate a dealer and schedule service.
.Request Roadside Assistance.
.Set a parking reminder with pin drop,
take a photo, make a note, and set a
timer.
.Connect with GMC on social media.
Features are subject to change. For myGMC
mobile app information and compatibility,
see my.gmc.com.
An active OnStar or connected service plan
may be required. A compatible device,
factory-installed remote start, and power
locks are required. Data rates apply. See
www.onstar.com for details and system
limitations.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Connected Services 415
Remote Services
Contact an OnStar Advisor to unlock the
doors or sound the horn and flash the
lamps.
Marketplace
OnStar Advisors can provide offers from
restaurants and retailers on your route, help
locate hotels, or book a room. These services
vary by market.
Diagnostics
By monitoring and reporting on the vehicle's
key systems, OnStar Advanced Diagnostics,
if equipped, provides a way to keep up on
maintenance. Capabilities vary by model.
See www.onstar.com for details and system
limitations. Features are subject to change.
For updates on feature capabilities, see
my.gmc.com. Message and data rates may
apply.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Index 421
H
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Hazard Warning Flashers . . . . . . . . . . . . . . . . .142
HD Radio Technology . . . . . . . . . . . . . . . . . . . . 156
Head Restraints . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Head-Up Display (HUD) . . . . . . . . . . . . . . . . . . . 132
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . 325
Daytime Running Lamps (DRL) . . . . . . . . . . 141
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Headlamps, Front Turn Signal,Sidemarker, and Parking Lamps . . . . . . 325
High-Beam On Light . . . . . . . . . . . . . . . . . . . . 127
High/Low Beam Changer . . . . . . . . . . . . . . . 141
Lamps On Reminder . . . . . . . . . . . . . . . . . . . 128
Heated Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Rear Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . 105
Ventilated Front Seats . . . . . . . . . . . . . . . . . . 56
Heater Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196, 197
High-Beam On Light . . . . . . . . . . . . . . . . . . . . . . 127 Hill
Descent Control (HDC) . . . . . . . . . . . . . . . . . 242
Descent Control Light . . . . . . . . . . . . . . . . . . 123
Hill and Mountain Roads . . . . . . . . . . . . . . . . . 212
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . . . . 240
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
How to Wear Seat Belts Properly . . . . . . . . . 59
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .196, 197
I
If the System Needs Service . . . . . . . . . . . . . . 171
Ignition Positions . . . . . . . . . . . . . . . . . . . . 221, 223
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Indicator Vehicle Ahead . . . . . . . . . . . . . . . . . . . . . . . . . 124
Indicators
Warning Lights and Gauges . . . . . . . . . . . . . 111
Infants and Young Children, Restraints . . . . .77
Information Publication Ordering . . . . . . . . . . . . . . . . . . . 404
Infotainment Using the System . . . . . . . . . . . . . . . . . . . . . . 152
Infotainment System . . . . . . . . . . . . . . . . . . . . 407
Inspection Multi-Point Vehicle . . . . . . . . . . . . . . . . . . . . 387
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . . . . 111
Instrument Panel Overview . . . . . . . . . . . . . . . . .5 Interior Rearview Mirrors . . . . . . . . . . . . . . . . . 40
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 2, 148
J
Jack
Auxiliary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Jump
Starting - North America . . . . . . . . . . . . . . . 367
K
Keyless EntryRemote (RKE) System Operation . . . . . 12, 14
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8, 11
L
Labeling, Tire Sidewall . . . . . . . . . . . . . . . . . . . 338
Lamps Auxiliary Roof Mounted Lamp . . . . . . . . . 144
Daytime Running (DRL) . . . . . . . . . . . . . . . . . 141
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Exterior Cargo . . . . . . . . . . . . . . . . . . . . . . . . . 144
Exterior Controls . . . . . . . . . . . . . . . . . . . . . . . 139
Exterior Lamps Off Reminder . . . . . . . . . . . 141
Exterior Lighting Battery Saver . . . . . . . . 147
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Fog . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
High/Low Beam Changer . . . . . . . . . . . . . . . 141
License Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . 327