
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 39
Folding Mirrors
Manual Folding Mirrors
If equipped, push the mirror toward the
vehicle to fold. Push the mirror outward to
return to its original position.
Manually fold the mirrors inward to prevent
damage when going through an automatic
car wash.
Power Folding Mirrors
If equipped, pressgto power fold the
mirrors. Press again to unfold. Resetting the Power Folding Mirrors
Reset the power folding mirrors if:
.The mirrors are accidentally obstructed
while folding.
.The mirrors are accidentally manually
folded/unfolded.
.The mirrors will not stay in the unfolded
position.
.The mirrors vibrate at normal driving
speeds.
Fold and unfold the mirrors one time using
the mirror controls to reset them to their
normal position. A noise may be heard
during the resetting of the power folding
mirrors. This sound is normal after a manual
folding operation.
Remote Mirror Folding
If equipped, press and holdQon the RKE
transmitter for approximately one second to
remotely fold the exterior mirrors. Press and
hold
Kon the RKE transmitter for
approximately one second to unfold. See
Remote Keyless Entry (RKE) System
Operation (Key Access) 012 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 014. This feature can be turned on or off. To
view available settings from the
infotainment screen, touch Settings >
Vehicle > Comfort and Convenience.
Heated Mirrors
If equipped with heated mirrors:
1REAR :
Press to heat the outside
mirrors.
See “Rear Window Defogger” underDual
Automatic Climate Control System 0197.
Automatic Dimming Mirror
If equipped, the driver outside mirror
automatically adjusts for the glare of the
headlamps from behind. This feature comes
on when the vehicle is started.
Blind Spot Mirrors
If equipped, there is a small convex mirror
built into the upper and outer corner of the
driver outside mirror. It can show objects
that may be in the vehicle's blind zone.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
44 Keys, Doors, and Windows
Once the horizontal guideline is in the
desired location, press and hold the button
for another three seconds and repeat the
above step for the vertical guideline
programing. To readjust the horizontal
location of the guidelines after adjusting the
vertical location, press and hold the button
for three seconds.
After eight seconds since the last button
press, the position of the guidelines is
locked into memory.
Windows{
Warning
Never leave a child, a helpless adult, or a
pet alone in a vehicle, especially with the
windows closed in warm or hot weather.
They can be overcome by the extreme
heat and suffer permanent injuries or
even death from heat stroke.
The vehicle aerodynamics are designed to
improve fuel economy performance. This
may result in a pulsing sound when either
rear window is down and the front windows
are up. To reduce the sound, open either a
front window or the sunroof, if equipped.
Manual Windows
If equipped, turn the hand crank on each
door to manually raise or lower the manual
windows.
Power Windows
{Warning
Children could be seriously injured or
killed if caught in the path of a closing
window. Never leave the Remote Keyless
Entry (RKE) transmitter or keys in a
vehicle with children. When there are
children in the rear seat, use the window
lockout button to prevent operation of
the windows. See Keys (Key Access)08
or
Keys (Keyless Access) 011.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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120 Instruments and Controls
will light either ON or OFF, or either the on
or off symbol, to let you know the status of
the front outboard passenger frontal airbag.
If the word ON or the on symbol is lit on
the passenger airbag status indicator, it
means that the front outboard passenger
frontal airbag is allowed to inflate.
If the word OFF or the off symbol is lit on
the passenger airbag status indicator, it
means that the passenger sensing system
has turned off the front outboard passenger
frontal airbag.
If, after several seconds, both status
indicator lights remain on, or if there are no
lights at all, there may be a problem with
the lights or the passenger sensing system.
See your dealer for service.
{Warning
If the airbag readiness light ever comes
on and stays on, it means that
something may be wrong with the airbag
system. To help avoid injury to yourself
or others, have the vehicle serviced right
away. SeeAirbag Readiness Light 0119
for more information, including important
safety information.
Charging System Light
The charging system light comes on briefly
when the ignition is turned on, but the
engine is not running, as a check to show
the light is working. It should go out when
the engine is started.
If the light stays on, or comes on while
driving, there may be a problem with the
electrical charging system. Have it checked
by your dealer. Driving while this light is on
could drain the battery.
When this light comes on, or is flashing, the
Driver Information Center (DIC) also displays
a message.
If a short distance must be driven with the
light on, be sure to turn off all accessories,
such as the radio and air conditioner. Find a
safe place to stop the vehicle.
Malfunction Indicator Lamp
(Check Engine Light)
This light is part of the vehicle’s emission
control on-board diagnostic system. If this
light is on while the engine is running, a
malfunction has been detected and the
vehicle may require service. The light should
come on to show that it is working when
the ignition is on and the engine is not
running. See Ignition Positions (Key Access)
0 221 or
Ignition Positions (Keyless Access) 0223.
Malfunctions are often indicated by the
system before any problem is noticeable.
Being aware of the light and seeking service
promptly when it comes on may prevent
damage.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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186 Infotainment System
Vehicle Account
Touch to view the vehicle account
information and to change the account
password.
Delete Profile
Touch to remove the profile from the
vehicle.
Touch Remove or Cancel.
Teen Driver
If equipped, this allows multiple keys to be
registered for beginner drivers to encourage
safe driving habits. When the vehicle is
started with a Teen Driver key, it will
automatically activate certain safety
systems, allow setting of some features, and
limit the use of others. The Report Card will
record vehicle data about driving behavior
that can be viewed later. When the vehicle
is started with a registered key, the Driver
Information Center (DIC) displays a message
that Teen Driver is active.
To access:1. Touch Settings on the Home Page, then touch Vehicle, and then Teen Driver. 2. Create a Personal Identification Number
(PIN) by choosing a four-digit PIN.
Re-enter the PIN to confirm. To change
the PIN, touch Change PIN.
The PIN is required to:
.Set up/Add or remove keys.
.Change Teen Driver settings.
.Change or clear the Teen Driver PIN.
.Access or delete Report Card data.
Set up/Add keys to activate Teen Driver and
assign restrictions to the key:
Any vehicle key can be registered, up to a
maximum of eight keys. Label the key to
tell it apart from the other keys.
For a pushbutton start system: 1. Start the vehicle.
2. For automatic transmissions, the vehicle must be in P (Park). For manual
transmissions, the vehicle must be
stopped with the parking brake set.
3. From the Settings menu, touch Vehicle and then Teen Driver.
4. Enter the PIN.
5. Place the remote key you wish to register in the transmitter pocket. The
key does not need to be the one that started the vehicle. See
Remote Keyless
Entry (RKE) System Operation (Key
Access) 012 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 014 for
transmitter pocket location.
6. From the Teen Driver menu, touch Setup Keys or Add/Remove Teen Driver Keys..If the remote key has not previously
been registered, the option to add
the key displays. Touch Add and a
confirmation message displays. Teen
Driver restrictions will be applied
whenever this remote key is used to
operate the vehicle.
.If the remote key has already been
registered, the option to remove the
key displays. If Remove is touched,
the remote key is no longer
registered. A confirmation message
displays, and Teen Driver restrictions
will not be applied if this remote key
is used to operate the vehicle.
In vehicles with a pushbutton start system,
if a Teen Driver and a non-Teen Driver key
are both present at start up, the vehicle will
recognize the non-Teen Driver key to start
the vehicle. The Teen Driver settings will not
be active.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Driving and Operating 203
Driving and Operating
Driving Information
Driving for Better Fuel Economy . . . . . . 204
Distracted Driving . . . . . . . . . . . . . . . . . . . . . 204
Defensive Driving . . . . . . . . . . . . . . . . . . . . . 205
Impaired Driving . . . . . . . . . . . . . . . . . . . . . . 205
Control of a Vehicle . . . . . . . . . . . . . . . . . . . 205
Braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Off-Road Recovery . . . . . . . . . . . . . . . . . . . . . 207
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . 207
Off-Road Driving . . . . . . . . . . . . . . . . . . . . . . 208
Driving on Wet Roads . . . . . . . . . . . . . . . . . . 211
Hill and Mountain Roads . . . . . . . . . . . . . . 212
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . . 212
If the Vehicle Is Stuck . . . . . . . . . . . . . . . . . 214
Vehicle Load Limits . . . . . . . . . . . . . . . . . . . . 215
Truck-Camper Loading Information . . . . . 219
Starting and Operating
New Vehicle Break-In . . . . . . . . . . . . . . . . . . 221
Ignition Positions (Key Access) . . . . . . . . . 221
Ignition Positions (Keyless Access) . . . . . 223
Starting the Engine . . . . . . . . . . . . . . . . . . . . 225
Engine Heater . . . . . . . . . . . . . . . . . . . . . . . . . 226
Retained Accessory Power (RAP) . . . . . . . 227
Shifting Into Park . . . . . . . . . . . . . . . . . . . . . . 227
Shifting out of Park . . . . . . . . . . . . . . . . . . . 228Parking over Things That Burn . . . . . . . . 229
Extended Parking . . . . . . . . . . . . . . . . . . . . . . 229
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . . . . . . . . . . . 229
Running the Vehicle While Parked . . . . . 230
Automatic Transmission
Automatic Transmission . . . . . . . . . . . . . . . 230
Manual Mode . . . . . . . . . . . . . . . . . . . . . . . . . 232
Tow/Haul Mode . . . . . . . . . . . . . . . . . . . . . . . 234
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 234
Brakes
Antilock Brake System (ABS) . . . . . . . . . . 238
Electric Parking Brake . . . . . . . . . . . . . . . . . 239
Brake Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . 240
Ride Control Systems
Traction Control/Electronic Stability
Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
Hill Descent Control (HDC) . . . . . . . . . . . . . 242
Driver Mode Control . . . . . . . . . . . . . . . . . . . 243
Locking Rear Axle . . . . . . . . . . . . . . . . . . . . . 244
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . 244
Driver Assistance Systems
Driver Assistance Systems . . . . . . . . . . . . . 246
Assistance Systems for Parking or Backing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Rear Vision Camera (RVC) . . . . . . . . . . . . . 248
Surround Vision System . . . . . . . . . . . . . . . 249
Park Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
Rear Cross Traffic Alert (RCTA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
Assistance Systems for Driving . . . . . . . . 257
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
Automatic Emergency Braking (AEB) . . . . . . . . . . . . . . . . . . . . . . . . 259
Side Blind Zone Alert (SBZA) . . . . . . . . . . 260
Lane Change Alert (LCA) . . . . . . . . . . . . . . . 261
Lane Departure Warning (LDW) . . . . . . . 262
Fuel
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Recommended Fuel . . . . . . . . . . . . . . . . . . . . 263
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . 264
Fuels in Foreign Countries . . . . . . . . . . . . . 264
Fuel Additives . . . . . . . . . . . . . . . . . . . . . . . . . 264
E85 or FlexFuel . . . . . . . . . . . . . . . . . . . . . . . . 264
Filling the Tank (Pickup Models) . . . . . . . 265
Filling the Tank (Chassis Cab and Box Delete Models) . . . . . . . . . . . . . . . . . . . . . . 266
Filling a Portable Fuel Container . . . . . . 268

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Driving and Operating 223
Caution
Use the correct key, make sure it is all
the way in—or pushed all the way in
toward the steering column when turning
off the vehicle —and turn it only with
your hand.
1 (ACC/ACCESSORY) : This position allows
features such as the infotainment system to
operate while the vehicle is off. It also
unlocks the steering column, if equipped
with a locking steering column. Use this
position if the vehicle must be pushed or
towed. See Retained Accessory Power (RAP)
0 227.
From ON/RUN, push the key all the way in
toward the steering column, then turn the
key to ACC/ACCESSORY.
If the key is left in ACC/ACCESSORY with the
engine off, the battery could drain and the
vehicle may not start.
A warning chime will sound when the driver
door is opened and the key is in the
ignition.
2 (ON/RUN) : This position can be used to
operate the electrical accessories and to
display some instrument cluster warning
and indicator lights. This position can also be used for service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may be
required for emission inspection purposes.
The switch stays in this position when the
engine is running. The transmission is also
unlocked in this position.
If the key is left in ON/RUN with the engine
off, the battery could drain and the vehicle
may not start.
3 (START) :
This is the position that starts
the engine. When the engine starts, release
the key. The ignition returns to ON/RUN for
driving.
Ignition Positions (Keyless Access)
Vehicles equipped with Keyless Access have
pushbutton starting.
The remote key must be in the vehicle for
the system to operate. If the pushbutton
start is not working, the vehicle may be
near a strong radio antenna signal causing
interference to the Keyless Access system.
See Remote Keyless Entry (RKE) System
Operation (Key Access) 012 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 014.
To shift out of P (Park), the ignition must be
on or in Service Mode, and the brake pedal
must be applied.
{Warning
Turning off the vehicle while moving may
cause loss of power assist in the brake
and steering systems and disable the
airbags. While driving, only shut the
vehicle off in an emergency.
Stopping the Engine/LOCK/OFF (No Indicator
Lights) : When the vehicle is stopped, press
ENGINE START/STOP once to turn the
engine off.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Driving and Operating 225
ignition is on, but the vehicle will not
be able to be driven. The engine will not
start in Service Mode. Press the ENGINE
START/STOP 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 0297.
Move the shift lever to 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. For Key Access vehicles, turn the ignition key to Start. When the engine starts, let
go of the key. For Keyless Access
vehicles, 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 driver may observe a minor, and
temporary, brake pedal kickback when
starting the vehicle. This is normal.
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), hold the ignition switch in
the START position to continue engine
cranking.Caution
Cranking the engine for long periods of
time, by returning the ignition to the
START position 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
holding the key in START or 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 key or 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

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Driving and Operating 227
Warning (Continued)
.Before starting the vehicle, unplug the
cord, reattach the cover to the plug,
and securely fasten the cord. Keep the
cord away from any moving parts.
5. Before starting the engine, be sure to unplug and store the cord.
The length of time the heater should remain
plugged in depends on several factors. Ask a
dealer in the area where you will be parking
the vehicle for the best advice on this.
Retained Accessory Power (RAP)
When the vehicle is turned from on to off,
the following features (if equipped) will
continue to function for up to 10 minutes,
or until the driver door is opened. These
features will also work when the vehicle is
on or in accessory mode:
.Infotainment System
.Power Windows (during RAP this
functionality will be lost when any door
is opened)
.Sunroof (during RAP this functionality will
be lost when any door is opened)
.Auxiliary Power Outlet
.Audio System
.OnStar System
Shifting Into Park
{Warning
Parking on grades with poor traction such
as ice, snow, mud, or gravel may cause
the vehicle to unintentionally move and
could result in injury, death, and/or
vehicle damage. If equipped with
four-wheel drive, use AUTO or 4 (HI) to
provide additional traction. Be sure to
apply the parking brake. See Electric
Parking Brake 0239 and
Four-Wheel Drive 0234.
{Warning
It can be dangerous to get out of the
vehicle if the shift lever is not fully in
P (Park) with the parking brake firmly set.
The vehicle can roll. If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured.
To be sure the vehicle will not move,
even when you are on fairly level ground,
(Continued)
Warning (Continued)
use the steps that follow. With
four-wheel drive, if the transfer case is in
N (Neutral), the vehicle will be free to
roll, even if the shift lever is in P (Park).
Be sure the transfer case is in a drive
gear. If towing a trailer, seeDriving
Characteristics and Towing Tips 0268.
1. Hold the brake pedal down, then set the parking brake. See Electric Parking Brake
0 239.
2. Move the shift lever into the P (Park) position by pulling the shift lever toward
you and moving it up as far as it will go.
3. Be sure the transfer case (if equipped) is in a drive gear –not in N (Neutral).
4. Turn the ignition off. For Key Access, push the ignition key in, towards the
steering column and then turn the
ignition off.
5. For Key Access, remove the key and take it with you. If you can leave the vehicle
with the ignition key in your hand, the
vehicle is in P (Park).
For Keyless Access, take the remote key
with you.