trailer GMC SIERRA 2023 Owners Manual

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
6 Introduction
1. Tow/Haul Mode (On Some Models). SeeDriver Mode Control 0243.
Automatic Transfer Case Control (If
Equipped). See Four-Wheel Drive 0234.
Driver Mode Control 0243 (If Equipped).
2. Air Vents 0201.
3. Head-Up Display (HUD) 0132 (If
Equipped).
4. Turn Signal Lever. See Turn and
Lane-Change Signals 0143.
Windshield Wiper/Washer 0106.
5. Instrument Cluster 0111.
6. Shift Lever. See Automatic Transmission
0 230.
Range Selection Mode. See Manual Mode
0 232.
7. Light Sensor. See Automatic Headlamp
System 0141.
8. Infotainment Controls. See Overview
0 149.
9. Climate Control Systems 0196 (If
Equipped).
Dual Automatic Climate Control System
0 197 (If Equipped).
10. Heated and Ventilated Front Seats 056
(If Equipped). 11.XPark Assist Switch (If Equipped). See
Assistance Systems for Parking or Backing
0 248.
5Power Release Tailgate (If
Equipped). See Tailgate026.
|Hazard Warning Flashers 0142.
gTraction Control/Electronic Stability
Control 0241.
-DC/AC Switch. See Power Outlets
0 107.
@Lane Departure Warning (LDW) 0262
(If Equipped).
5Hill Descent Control Switch (If
Equipped). See Hill Descent Control (HDC)
0 242.
jPower Assist Steps 033 (If
Equipped).
LExpress Window Down Button (If
Equipped). See Power Windows 044.
Tow/Haul Mode 0234 (On Some
Models).
Exhaust Brake (If Equipped). See Duramax
Diesel Supplement.
Power Take-Off (PTO) (If Equipped). See
Duramax Diesel Supplement. 12. Power Outlet (Alternating Current) (If
Equipped). See Power Outlets0107.
13. Power Outlets 0107.
14. USB Port 0158.
15. Wireless Charging 0109 (If Equipped).
16. Trailer Brake Control Panel (If Equipped). See“Integrated Trailer Brake Control
System” underTowing Equipment 0276.
17. ENGINE START/STOP. See Ignition
Positions (Key Access) 0221 or
Ignition Positions (Keyless Access) 0223.
18. Steering Wheel Controls 0151 (If
Equipped).
Driver Information Center (DIC) Controls.
See Driver Information Center (DIC) (Base
Level) 0128 or
Driver Information Center (DIC) (Midlevel
and Uplevel) 0130.
19. Horn 0106.
20. Hood Release. See Hood0303.
21. Steering Wheel Adjustment 0105 (Out
of View).
22. Cruise Control 0244.
Forward Collision Alert (FCA) System
0 257 (If Equipped).
Heated Steering Wheel 0105 (If
Equipped).

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
8 Keys, Doors, and Windows
Keys, Doors, and
Windows
Keys and Locks
Keys (Key Access) . . . . . . . . . . . . . . . . . . . . . . . 8
Keys (Keyless Access) . . . . . . . . . . . . . . . . . . . 11
Remote Keyless Entry (RKE) System . . . . 12
Remote Keyless Entry (RKE) SystemOperation (Key Access) . . . . . . . . . . . . . . . . 12
Remote Keyless Entry (RKE) System Operation (Keyless Access) . . . . . . . . . . . . 14
Remote Vehicle Start . . . . . . . . . . . . . . . . . . . 22
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Power Door Locks . . . . . . . . . . . . . . . . . . . . . . 24
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . 24
Automatic Door Locks . . . . . . . . . . . . . . . . . . 24
Lockout Protection . . . . . . . . . . . . . . . . . . . . . . 25
Safety Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Doors
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Transporting Items That Can Catch Fire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Power Assist Steps . . . . . . . . . . . . . . . . . . . . . 33
Vehicle Security
Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . 34
Vehicle Alarm System . . . . . . . . . . . . . . . . . . 34
Steering Column Lock . . . . . . . . . . . . . . . . . . . 35 Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Immobilizer Operation . . . . . . . . . . . . . . . . . . 35
Exterior Mirrors
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 36
Manual Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 37
Trailer-Tow Mirrors . . . . . . . . . . . . . . . . . . . . . 37
Power Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Folding Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 39
Heated Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 39
Automatic Dimming Mirror . . . . . . . . . . . . . 39
Blind Spot Mirrors . . . . . . . . . . . . . . . . . . . . . . 39
Reverse Tilt Mirrors . . . . . . . . . . . . . . . . . . . . 40
Interior Mirrors
Interior Rearview Mirrors . . . . . . . . . . . . . . . 40
Manual Rearview Mirror . . . . . . . . . . . . . . . . 41
Automatic Dimming Rearview Mirror . . . 41
Rear Camera Mirror . . . . . . . . . . . . . . . . . . . . . 41
Truck Bed Camera Rearview Mirror . . . . . 43
Windows
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Manual Windows . . . . . . . . . . . . . . . . . . . . . . 44
Power Windows . . . . . . . . . . . . . . . . . . . . . . . . 44
Rear Windows . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Sun Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Roof
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Keys and Locks
Keys (Key Access)
{Warning
Leaving children in a vehicle with the
ignition 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 keys in the ignition, and children or
others could be caught in the path of a
closing window. Do not leave children in
a vehicle with the ignition key.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
30 Keys, Doors, and Windows
.Press5on the center stack.
.Press the lower touch pad on the tailgate
handle after unlocking all doors. Use the
top of the tailgate to pull against if
assistance is required.
To close the primary tailgate, firmly push it
upward until it latches. Pull it back to be
sure it is latched securely.
To open the inner tailgate, press the upper
touch pad on the tailgate handle after
unlocking all doors. Pull the top of the
tailgate to open.
Caution
Do not open the inner tailgate with the
primary tailgate open if there is a hitch
ball or trailer attached. This may damage
the tailgate.
To close the inner tailgate with the primary
tailgate closed, firmly push or pull it upward
until it latches. Pull it back to be sure it is
latched securely.
To close the inner tailgate with the primary
tailgate open:
.Hold the primary tailgate and firmly close
the inner tailgate.
.Raise the inner tailgate so it meets the
primary tailgate and close together at the
same time.
When using the tailgate step as a load stop,
the load must be secured as the load could
shift. See Cargo Tie-Downs 0102.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
36 Keys, Doors, and Windows
located in the center console. SeeRemote
Keyless Entry (RKE) System Operation (Key
Access) 012 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 014.
If the ignition mode will not change with
the other transmitter or with the
transmitter in the transmitter pocket, your
vehicle needs service. If the ignition does
change modes, the first transmitter may be
faulty. See your dealer who can service the
theft-deterrent system and have a new RKE
transmitter programmed to the vehicle.
It is possible for the immobilizer system to
learn new or replacement RKE transmitters.
Up to eight transmitters can be
programmed for the vehicle. To program
additional transmitters, see "Programming
Transmitters to the Vehicle" under Remote
Keyless Entry (RKE) System Operation (Key
Access) 012 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 014
Do not leave the transmitter or device that
disarms or deactivates the vehicle theft
system in the vehicle. When equipped with a key, if the engine
still does not start, and the key appears to
be undamaged, try another ignition key.
It may be necessary to check the fuse. See
Fuses and Circuit Breakers
0329. If the
engine still does not start with the other
key, the vehicle needs service. If the vehicle
does start, the first key may be faulty. See
your dealer. It is possible for the
immobilizer system to learn new or
replacement keys. Up to eight keys can be
programmed for the vehicle. To program
additional keys, see Keys (Key Access)08or
Keys (Keyless Access) 011. Do not leave the
key or device that disarms or deactivates
the vehicle theft system in the vehicle.
See your dealer to get a new key blank cut
exactly as the ignition key that operates the
system.Exterior Mirrors
Convex Mirrors
{Warning
A convex mirror can make things, like
other vehicles, look farther away than
they really are. If you cut too sharply
into the right lane, you could hit a
vehicle on the right. Check the inside
mirror or glance over your shoulder
before changing lanes.
Standard Mirrors
The passenger side mirror is convex shaped.
A convex mirror surface is curved so more
can be seen from the driver seat.
Trailer-Tow Mirrors
The upper portion of both the driver and
passenger mirrors is flat.
The lower portion of both the driver and
passenger mirrors is convex. A convex mirror
surface is curved so more can be seen from
the driver seat. The lower portion is
adjusted manually.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Keys, Doors, and Windows 37
Manual Mirrors
If equipped, adjust manual mirrors by
moving the mirror up and down or left to
right to see a little of the side of the vehicle
and to have a clear view behind the vehicle.
Using hood-mounted air deflectors and
add-on convex mirror attachments could
decrease mirror performance.
Trailer-Tow Mirrors
Extending Mirrors
Trailer tow mirrors can extend out for better
visibility when towing a trailer.
Manual Extend :If equipped, grasp the
mirror housing firmly and pull back in one
motion, arching slightly toward the rear of
the vehicle.
To return the mirror to its original position,
reverse the motion.
Power Extend : If equipped, press the power
extend button to fully extend the mirror.
Press again to retract.
Resetting the Power Extend Mirrors
Reset the power extend mirrors if:
.The mirrors are accidentally obstructed
while extending/retracting.
.The mirrors are accidentally manually
extended/retracted.
.The mirrors vibrate at normal driving
speeds.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
38 Keys, Doors, and Windows
If a popping noise from the mirror is heard,
this sound is normal as the manual detents
are aligning after a manual extend/retract
operation has occurred.
Auxiliary Cargo Mirror Lamps
If equipped, cargo mirror lamps face
rearward to provide more light on the sides
of the vehicle, if needed. SeeExterior Cargo
Lamps 0144.
Advanced Trailering Vision System Side
Cameras
If equipped, the Advanced Trailering Vision
System side cameras are on the bottom of
the outside mirrors. See “Surround Vision
(360 Degrees)” underAssistance Systems for
Parking or Backing 0248.Power Mirrors
To adjust each mirror:
1. Press
jor|to select the driver or
passenger side mirror. The indicator light
will illuminate.
2. Press the arrows on the control pad to move the mirror in the desired direction.
3. Adjust each outside mirror so that a little of the vehicle and the area behind it can
be seen.
4. Press
jor|again to deselect the
mirror. Turn Signal Indicator
If equipped, the mirror has turn signal
indicator lights, which flash in the direction
of the turn or lane change.
Task Lighting
If equipped, task lighting projects light from
the outside mirrors to the sides of the
vehicle. See
Task Lighting 0144.
Puddle Lamps
If equipped, puddle lamps project light from
the bottom of the mirror to the area of
ground below the driver and passenger
doors. See Entry Lighting 0146 and
Exit Lighting 0146.
Memory Mirrors
The vehicle may have memory mirrors. See
Memory Seats 053.
Lane Change Alert (LCA)
The vehicle may have LCA. See Lane Change
Alert (LCA) 0261.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Keys, Doors, and Windows 43
See your dealer for service if a blue screen
and
3are displayed in the mirror, and
the display shuts off. Also, push the tab as
indicated to return to the automatic
dimming mode.
The Rear Camera Mirror may not work
properly or display a clear image if:
.There is glare from the sun or headlamps.
This may obstruct objects from view.
If needed, push the tab to turn off the
display.
.Dirt, snow, or other debris blocks the
camera lens. Clean the lens with a soft
damp cloth.
.The camera’s mounting on the vehicle has
been damaged, and/or the position or the
mounting angle of the camera has
changed.
Truck Bed Camera Rearview
Mirror
If equipped, this automatic dimming mirror
provides a video image, when activated, to
allow the driver to momentarily check the
pickup bed area contents or to align and
attach a gooseneck or fifth-wheel trailer.
.Push the button at the bottom of the
mirror once to activate the display.
.Push the button a second time to zoom
the camera’s view.
.Push the button a third time to
deactivate the display.
When the vehicle is in R (Reverse) and
button has been pressed, the display will
remain on until the driver deactivates it.
When not in R (Reverse), the video image
will time out after eight seconds.
When in Zoomed Mode, the display features
guidelines to help the driver align the
vehicle when attaching a trailer. Both the
horizontal and vertical guideline’s position
can be adjusted by the driver.
To adjust the position of the horizontal
guideline, press and hold the button for
eight seconds until it starts blinking. Each
subsequent button press scrolls the position
of this line through its range of possible
settings.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Instruments and Controls 121
Caution
If the vehicle is driven continually with
this light on, the emission control system
may not work as well, the fuel economy
may be lower, and the vehicle may not
run smoothly. This could lead to costly
repairs that might not be covered by the
vehicle warranty.
Caution
Modifications to the engine, transmission,
exhaust, intake, or fuel system, or the
use of replacement tires that do not
meet the original tire specifications, can
cause this light to come on. This could
lead to costly repairs not covered by the
vehicle warranty. This could also affect
the vehicle’s ability to pass an Emissions
Inspection/Maintenance test. See
Accessories and Modifications0302.
If the light is flashing : A malfunction has
been detected that could damage the
emission control system and increase vehicle
emissions. Diagnosis and service may be
required. To help prevent damage, reduce vehicle
speed and avoid hard accelerations and
uphill grades. If towing a trailer, reduce the
amount of cargo being hauled as soon as
possible.
If the light continues to flash, find a safe
place to park. Turn the vehicle off and wait
at least 10 seconds before restarting the
engine. If the light is still flashing, follow
the previous guidelines and see your dealer
for service as soon as possible.
If the light is on steady :
A malfunction has
been detected. Diagnosis and service may be
required.
Check the following:
.If fuel has been added to the vehicle
using the capless funnel adapter, make
sure that it has been removed. See
“Filling the Tank with a Portable Gas Can”
under Filling the Tank (Chassis Cab and
Box Delete Models) 0266 or
Filling the Tank (Pickup Models) 0265.
The diagnostic system can detect if the
adapter has been left installed in the
vehicle, allowing fuel to evaporate into
the atmosphere. A few driving trips with
the adapter removed may turn off the
light.
.Poor fuel quality can cause inefficient
engine operation and poor driveability,
which may go away once the engine is
warmed up. If this occurs, change the fuel
brand. It may require at least one full
tank of the proper fuel to turn the light
off. See Recommended Fuel 0263.
If the light remains on, see your dealer.
Emissions Inspection and Maintenance
Programs
If the vehicle requires an Emissions
Inspection/Maintenance test, the test
equipment will likely connect to the
vehicle's Data Link Connector (DLC).
The DLC is under the instrument panel to
the left of the steering wheel. Connecting
devices that are not used to perform an
Emissions Inspection/Maintenance test or to
service the vehicle may affect vehicle

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Instruments and Controls 125
Trailer Sway Control Light (Uplevel
Cluster)
This light will flash when Trailer Sway
Control is active. SeeTrailer Sway Control
(TSC) 0285.
Electronic Stability Control (ESC)
Off Light
This light comes on briefly when the vehicle
is turned on to show that the light is
working. If it does not come on then, have
it fixed so it will be ready to warn you if
there is a problem. This light comes on when the Electronic
Stability Control (ESC) system is turned off.
If ESC is off, the Traction Control System
(TCS) is also off. To turn ESC off and on, see
Traction Control/Electronic Stability Control
0
241.
If ESC and TCS are off, the systems do not
assist in controlling the vehicle. Adjust
driving accordingly.
Engine Coolant Temperature
Warning Light
This light comes on briefly while starting
the vehicle.
If it does not, have the vehicle serviced by
your dealer. If the system is working
normally the indicator light goes off.
Caution
The engine coolant temperature warning
light indicates that the vehicle has
overheated. Driving with this light on can
damage the engine and it may not be
covered by the vehicle warranty. See
Engine Overheating 0313.
The engine coolant temperature warning
light comes on when the engine has
overheated.
If this happens, pull over and let the engine
idle. See Engine Overheating 0313.
Driver Mode Control Light
This light comes on when Snow Mode is
selected.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
132 Instruments and Controls
Engine Hours (Hourmeter) :Shows the total
number of hours the engine has run. This
display also shows the engine idle hours.
Transmission Fluid Temperature : Shows the
temperature of the automatic transmission
fluid in either degrees Celsius (°C) or degrees
Fahrenheit (°F).
Trailer Brake : On vehicles with the
Integrated Trailer Brake Control (ITBC)
system, the trailer brake display appears in
the DIC.
TRAILER GAIN shows the trailer gain setting.
This setting can be adjusted from 0.0 to 10.0
with either a trailer connected or
disconnected.
TRAILER OUTPUT shows the power output to
the trailer any time a trailer with electric
brakes is connected. Output is displayed as a
bar graph. Dotted lines may appear in the
OUTPUT display if a trailer is not connected.
Off Road : Displays vehicle pitch and roll
information, road wheel angle, and
four-wheel drive (4WD) status.
Follow Distance : If equipped, the current
follow time to the vehicle ahead is displayed
as a time value on this page. Driver Assistance :
If equipped, shows
information for Lane Departure Warning
(LDW) and Forward Collision Alert (FCA).
Info Page Options : Scroll to choose which
info pages appear on the DIC. Press the
thumbwheel to select or deselect.
Blank Page : Shows no information.
Head-Up Display (HUD)
{Warning
If the HUD image is too bright or too
high in your field of view, it may take
you more time to see things you need to
see when it is dark outside. Be sure to
keep the HUD image dim and placed low
in your field of view.
If equipped with HUD, some information
about the operation of the vehicle is
projected onto the windshield. The image is
projected through the HUD lens on top of
the instrument panel. The information
appears as an image focused out toward the
front of the vehicle.
Caution
If you try to use the HUD image as a
parking aid, you may misjudge the
distance and damage your vehicle. Do not
use the HUD image as a parking aid.
The HUD information can be displayed in
various languages. The speedometer reading
and other numerical values can be displayed
in either English or metric units.
The language selection is changed through
the radio, and the units of measurement are
changed through the instrument cluster. See
Settings 0182 and “Options” under
Instrument Cluster 0111.
HUD Display on the Windshield