child lock CHEVROLET SILVERADO 2500HD 2021 Owner's Manual

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
2 Introduction
Helm, Incorporated
Attention: Customer Service
47911 Halyard Drive
Plymouth, MI 48170
USA
Using this Manual
To quickly locate information about the
vehicle, use the Index in the back of the
manual. It is an alphabetical list of what is
in the manual and the page number where
it can be found.
Danger, Warning, and Caution
Warning messages found on vehicle labels
and in this manual describe hazards and
what to do to avoid or reduce them.
{Danger
Danger indicates a hazard with a high
level of risk which will result in serious
injury or death.
{Warning
Warning indicates a hazard that could
result in injury or death.
Caution
Caution indicates a hazard that could
result in property or vehicle damage.
A circle with a slash through it is a safety
symbol which means“Do not,” “Do not do
this,” or“Do not let this happen.”
Symbols
The vehicle has components and labels that
use symbols instead of text. Symbols are
shown along with the text describing the
operation or information relating to a
specific component, control, message, gauge,
or indicator.
M:Shown when the owner’s manual has
additional instructions or information.
*: Shown when the service manual has
additional instructions or information.
0: Shown when there is more information
on another page — “see page.” Vehicle Symbol Chart
Here are some additional symbols that may
be found on the vehicle and what they
mean. See the features in this manual for
information.
u:
Air Conditioning System
G:Air Conditioning Refrigerant Oil
9:Airbag Readiness Light
!:Antilock Brake System (ABS)
$:Brake System Warning Light
9:Dispose of Used Components Properly
P:Do Not Apply High Pressure Water
B:Engine Coolant Temperature
_:Flame/Fire Prohibited
H: Flammable
[:Forward Collision Alert
R:Fuse Block Cover Lock Location
+:Fuses
j:ISOFIX/LATCH System Child Restraints

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Keys, Doors, and Windows 7
Keys, Doors, and
Windows
Keys and Locks
Keys (Key Access) . . . . . . . . . . . . . . . . . . . . . . . . 7
Keys (Keyless Access) . . . . . . . . . . . . . . . . . . . . 9
Remote Keyless Entry (RKE) System . . . . 10
Remote Keyless Entry (RKE) SystemOperation (Key Access) . . . . . . . . . . . . . . . 10
Remote Keyless Entry (RKE) System Operation (Keyless Access) . . . . . . . . . . . . 13
Remote Vehicle Start . . . . . . . . . . . . . . . . . . . 20
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Power Door Locks . . . . . . . . . . . . . . . . . . . . . . . 22
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . 22
Automatic Door Locks . . . . . . . . . . . . . . . . . . 22
Lockout Protection . . . . . . . . . . . . . . . . . . . . . . 22
Safety Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Doors
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Power Assist Steps . . . . . . . . . . . . . . . . . . . . . 26
Vehicle Security
Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . 27
Vehicle Alarm System . . . . . . . . . . . . . . . . . . 27
Steering Column Lock . . . . . . . . . . . . . . . . . . 28
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Immobilizer Operation . . . . . . . . . . . . . . . . . . 29
Exterior Mirrors
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 30
Manual Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 30
Trailer-Tow Mirrors . . . . . . . . . . . . . . . . . . . . . 30
Power Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Folding Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 32
Heated Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 33
Automatic Dimming Mirror . . . . . . . . . . . . . 33
Blind Spot Mirrors . . . . . . . . . . . . . . . . . . . . . . 33
Reverse Tilt Mirrors . . . . . . . . . . . . . . . . . . . . . 34
Interior Mirrors
Interior Rearview Mirrors . . . . . . . . . . . . . . . 34
Manual Rearview Mirror . . . . . . . . . . . . . . . . 34
Automatic Dimming Rearview Mirror . . . 34
Rear Camera Mirror . . . . . . . . . . . . . . . . . . . . 34
Truck Bed Camera Rearview Mirror . . . . . 37
Windows
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Manual Windows . . . . . . . . . . . . . . . . . . . . . . . 38
Power Windows . . . . . . . . . . . . . . . . . . . . . . . . 38
Rear Windows . . . . . . . . . . . . . . . . . . . . . . . . . 40
Sun Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Roof
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
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.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Keys, Doors, and Windows 9
1. Insert the original, already programmedkey in the ignition and turn the
ignition on.
2. Turn the ignition off, and remove the key.
3. Quickly, within five seconds, insert the second original already programmed key
in the ignition and turn the ignition on.
4. Turn the ignition off, and remove the key.
5. Insert the key to be programmed and turn the ignition on within five seconds.
6. After a few seconds, the security light will turn off once the key has been
programmed.
7. Repeat Steps 1–5 if additional keys are to be programmed.
If a key is lost or damaged, see your dealer
to have a new key made.
Programming without Recognized Keys
Program a new key to the vehicle when a
recognized key is not available. Canadian
regulations require that owners see their
dealer.
If two currently recognized keys are not
available, follow this procedure to program
the first key. This procedure will take approximately
30 minutes to complete for the first key.
The vehicle must be off and all of the keys
you wish to program must be with you.
1. Insert the new vehicle key into the ignition.
2. Turn the ignition on. The security light will come on.
3. Wait 10 minutes until the security light turns off.
4. Turn the ignition off.
5. Repeat Steps 2–4 two more times. After the third time, turn the ignition on; the
key is learned and all previously known
keys will no longer work with the
vehicle.
6. To learn a second key, turn the ignition off, insert the second key to be learned,
and turn the ignition on.
After two keys are learned, the remaining
keys can be learned by following the
procedure in “Programming with Two
Recognized Keys.”
The key has a bar-coded key tag that the
dealer or qualified locksmith can use to
make new keys. Store this information in a
safe place, not in the vehicle. See your dealer if a replacement key or
additional key is needed.
If it becomes difficult to turn a key, inspect
the key blade for debris. Periodically clean
with a brush or pick.
If locked out of the vehicle, see
Roadside
Assistance Program 0404.
With an active OnStar or connected service
plan, an OnStar Advisor may remotely
unlock the vehicle. See OnStar Overview
0 412.
Keys (Keyless Access)
{Warning
Leaving children in a vehicle with an
ignition key or Remote Keyless Entry
(RKE) transmitter is dangerous and
children or others could be seriously
injured or killed. They could operate the
power window or other controls or make
the vehicle move. The windows will
function with the key in the ignition or
with the RKE transmitter in the vehicle,
and children or others could be caught in
(Continued)

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
10 Keys, Doors, and Windows
Warning (Continued)
the path of a closing window. Do not
leave children in a vehicle with the
ignition key or an RKE transmitter.
If the vehicle has the Keyless Access system,
the transmitter has a button on the side of
the transmitter used to remove the key.
This key is used for the driver door and
glove box.
Press the button to remove the key. Never
pull the key out without pressing the
button.
See your dealer if a replacement key or
additional key is needed.
If it becomes difficult to turn a key, inspect
the key blade for debris. Periodically clean
with a brush or pick.
With an active OnStar or connected service
plan, an OnStar Advisor may remotely
unlock the vehicle. SeeOnStar Overview
0 412.
If locked out of the vehicle, see Roadside
Assistance Program 0404. If equipped with memory seats, RKE
transmitters 1 and 2 are linked to seating
positions of memory 1 or 2. See
Memory
Seats 046.
Remote Keyless Entry (RKE)
System
See Radio Frequency Statement 0409.
If there is a decrease in the Remote Keyless
Entry (RKE) operating range:
.Check the distance. The transmitter may
be too far from the vehicle.
.Check the location. Other vehicles or
objects may be blocking the signal.
.Check the transmitter's battery. See
“Battery Replacement” later in this
section.
.If the transmitter is still not working
correctly, see your dealer or a qualified
technician for service.
Remote Keyless Entry (RKE)
System Operation (Key Access)
The RKE transmitter functions may work up
to 60 m (197 ft) away from the vehicle.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Keys, Doors, and Windows 21
Door Locks
{Warning
Unlocked doors can be dangerous.
.Passengers, especially children, can
easily open the doors and fall out of a
moving vehicle. The doors can be
unlocked and opened while the vehicle
is moving. The chance of being thrown
out of the vehicle in a crash is
increased if the doors are not locked.
So, all passengers should wear seat
belts properly and the doors should be
locked whenever the vehicle is driven.
.Young children who get into unlocked
vehicles may be unable to get out.
A child can be overcome by extreme
heat and can suffer permanent injuries
or even death from heat stroke.
Always lock the vehicle whenever
leaving it.
.Outsiders can easily enter through an
unlocked door when you slow down
or stop the vehicle. Locking the doors
can help prevent this from happening.There are several ways to lock and unlock
the vehicle.
From outside:
.Use the Remote Keyless Entry (RKE)
transmitter.
.Use Keyless Access, if equipped.
.Use the key in the driver door or the
passenger door, if equipped.
From inside, use the power door locks or the
manual door locks. To lock the door with
the manual door locks, push down on the
manual lock knob.
From inside, pull the door handle once to
unlock the door. Pull the handle again to
open the door.
See Vehicle Alarm System 027. Keyless Access
If equipped, the remote key must be within
1 m (3 ft) of the tailgate or door being
opened or locked. Press the button on the
door handle to open. See
“Keyless Access
Operation” inRemote Keyless Entry (RKE)
System Operation (Key Access) 010 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 013.
Free-Turning Locks
The door key lock cylinder turns freely when
either the wrong key is used, or the correct
key is not fully inserted. The free-turning
door lock feature prevents the lock from
being forced open. To reset the lock, turn it
to the vertical position with the correct key

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Keys, Doors, and Windows 23
Lockout Protection can be manually
overridden with the driver door open by
pressing and holding
Qon the power door
lock switch.
Open Door Anti-Lockout
If equipped, the Open Door Anti-Lockout is
turned on and the vehicle is off, the driver
door is open, and locking is requested, all
the doors will lock and the driver door will
unlock. The Open Door Anti-Lockout feature
can be turned on or off. See Vehicle
Personalization 0126.
Safety Locks
The rear door safety locks prevent
passengers from opening the rear doors
from inside the vehicle.
The safety lock is on the inside edge of the
rear doors. To use the safety lock:
1. Move the lever down to the lock position.
2. Close the door.
3. Do the same for the other rear door.
To open a rear door when the safety lock
is on: 1. Unlock the door by activating the inside handle, by pressing the power door
unlock switch, or by using the Remote
Keyless Entry (RKE) transmitter.
2. Open the door from the outside. When the safety lock is enabled, adults and
older children will not be able to open the
rear door from the inside. Cancel the safety
locks to enable the doors to open from the
inside.
To cancel the safety lock:
1. Unlock the door and open it from the outside.
2. Move the lever up to unlock. Do the same for the other door.Doors
Tailgate
Manual Tailgate
{Warning
It is extremely dangerous to ride on the
tailgate, even when the vehicle is
operated at low speeds. People riding on
the tailgate can easily lose their balance
and fall in response to vehicle maneuvers.
Falling from a moving vehicle may result
in serious injuries or death. Do not allow
people to ride on the tailgate. Be sure
everyone in your vehicle is in a seat and
using a seat belt properly.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Keys, Doors, and Windows 27
Warning (Continued)
hands or other body parts between the
extended power assist step and the
vehicle.
If equipped, the power assist steps will
deploy when the door is opened and
automatically retract three seconds after the
door is closed. The power assist steps will
retract immediately if the vehicle starts
moving.
Disable the power assist steps before jacking
or placing any object under the vehicle. Too
much ice buildup may prevent deployment
of the power assist steps. Check the step
position before exiting the vehicle. If this
happens, disable the power assist steps,
clear the ice, then enable the assist steps
and confirm normal function prior to use.
Keep hands, children, pets, objects, and
clothing clear of the power assist steps
when in motion. The steps will reverse
direction if they encounter an obstruction
when opening or closing. Remove the
obstruction, then open and close the door
on the same side to complete the motion of the assist steps. If the obstruction is not
cleared. the assist steps remain extended
while driving.
To extend both power assist steps
for cleaning, press
jwhile the vehicle is
in P (Park) or N (Neutral). Press
jagain
to retract them. The Driver Information
Center (DIC) will display a message.
Enable/Disable
Press and hold
jfor four seconds to lock
and disable the power assist steps. Press
and hold
jfor four seconds again to
enable them. The DIC will display a
message.
Vehicle Security
This vehicle has theft-deterrent features;
however, they do not make the vehicle
impossible to steal.
Vehicle Alarm System
The indicator light, on the instrument panel
near the windshield, indicates the status of
the system.
Off : Alarm system is disarmed.
On Solid : Vehicle is secured during the
delay to arm the system.
Fast Flash : Vehicle is unsecured. A door or
the hood is open.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Keys, Doors, and Windows 37
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. 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.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
38 Keys, Doors, and Windows
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. SeeKeys (Key
Access) 07or
Keys (Keyless Access) 09.
The power windows work when the ignition
is on, in ACC/ACCESSORY, or when Retained
Accessory Power (RAP) is active. See
Retained Accessory Power (RAP) 0229.
Using the window switch, press to open or
pull to close the window.
The windows may be temporarily disabled if
they are used repeatedly within a
short time.
Window Lockout
With Power Folding Mirrors, Without Similar
This feature stops the rear door passenger
window switches from working except from
the driver position.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Seats and Restraints 43
Adjust the head restraint so that the top of
the restraint is at the same height as the
top of the occupant's head. This position
reduces the chance of a neck injury in a
crash.
To raise or lower the head restraint, press
the button on the side of the head restraint
and pull up or push the head restraint down
and release the button.
Pull and push on the head restraint after the
button is released to make sure that it is
locked in place.
The front seat outboard head restraints are
not removable.
Rear Head Restraints
The vehicle’s rear seat has head restraints in
the outboard seating positions that cannot
be adjusted.
The head restraint can be folded forward to
allow for better visibility when the rear seat
is unoccupied. To fold the head restraint,
press the button on the side of the head
restraint.
When an occupant is in the seat, always
return the head restraint to the upright
position until it locks into place. Push and
pull on the head restraint to make sure that
it is locked.If you are installing a child restraint in the
rear seat, see
Lower Anchors and Tethers for
Children (LATCH System) 074.
Center Headrest
The vehicle’s rear seat may be equipped
with a headrest in the center seating
position that cannot be adjusted.
If you are installing a child restraint in the
rear seat, see Lower Anchors and Tethers for
Children (LATCH System) 074.
Front Seats
Seat Adjustment
{Warning
You can lose control of the vehicle if you
try to adjust a driver seat while the
vehicle is moving. Adjust the driver seat
only when the vehicle is not moving.