engine CHEVROLET SILVERADO 2500HD 2021 User Guide

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
28 Keys, Doors, and Windows
Slow Flash :Alarm system is armed.
Arming the Alarm System
1. Turn off the vehicle.
2. Lock the vehicle in one of two ways:
.Use the RKE transmitter.
.With a door open, pressQon the
interior of the door.
3. After 30 seconds, the alarm system will arm and the indicator light will begin to
slowly flash. Pressing
Qon the RKE
transmitter a second time will bypass
the 30-second delay and immediately
arm the alarm system.
The vehicle alarm system will not arm if the
doors are locked with the key.
If the driver door is opened without first
unlocking with the RKE transmitter, the horn
will chirp and the lights will flash to indicate
pre-alarm. If the vehicle is not started,
or the door is not unlocked by pressing
K
on the RKE transmitter during the 10-second
pre-alarm, the alarm will be activated.
The alarm will also be activated if a
passenger door or the hood is opened
without first disarming the system. When
the alarm is activated, the turn signals flash and the horn sounds for about 30 seconds.
The alarm system will then re-arm to
monitor for the next unauthorized event.
Disarming the Alarm System
To disarm the alarm system or turn off the
alarm if it has been activated:
.PressKon the RKE transmitter.
.Start the vehicle.
To avoid setting off the alarm by mistake:
.Lock the vehicle after all occupants have
exited.
.Always unlock a door with the RKE
transmitter.
Unlocking the driver door with the key
will not disarm the system or turn off the
alarm.
How to Detect a Tamper Condition
IfKis pressed on the RKE transmitter and
the horn chirps three times, an alarm
occurred previously while the alarm system
was armed.
If the alarm has been activated, a message
will appear on the DIC.
Steering Column Lock
If equipped, the steering column lock is a
theft-deterrent device. This feature locks the
steering column when the vehicle is turned
off and the driver door is opened, or when
the driver door is opened and then the
vehicle is turned off. The steering column
unlocks when the vehicle is turned on.
The Driver Information Center (DIC) may
display one of these messages:
.A message to service the steering column
lock indicates that an issue has been
detected with the column lock feature
and the vehicle should be serviced.
.A message that the steering column is
locked indicates that the engine is
running, but the steering column is still
locked. It is normal for the column to be
locked during a remote start, but the
column should unlock after the brake
pedal is pressed and the vehicle is started.
No message will display during a remote
start.
.A message that the steering wheel must
be turned and the vehicle must be started
again indicates that the column lock
mechanism is bound, the column locking
device was unable to unlock the steering

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Keys, Doors, and Windows 29
column, and the vehicle did not start.
If this happens, immediately turn the
steering wheel from side to side to
unbind the column lock. If this does not
unlock the steering column, turn the
vehicle off and open the driver door to
reset the system. Then turn the vehicle
on and immediately turn the steering
wheel side to side for about 15 seconds.
In some cases, it may take significant
force to unbind the column.
To keep the steering column from binding,
straighten the front wheels before turning
off the vehicle.
Immobilizer
See Radio Frequency Statement 0409.
Immobilizer Operation
This vehicle has a passive theft-deterrent
system. The system does not have to be manually
armed or disarmed.
The vehicle is automatically immobilized
when the vehicle is turned off.
The system is automatically disarmed when
the ignition is turned from off to on.
The security light, in the instrument cluster,
comes on if there is a problem with arming
or disarming the theft-deterrent system.
The system has one or more RKE
transmitters matched to an immobilizer
control unit in your vehicle. Only a correctly
matched RKE transmitter will start the
vehicle. If the transmitter is ever damaged,
you may not be able to start your vehicle.
When trying to start the vehicle, the
security light may come on briefly when the
ignition is turned on. If the engine does not
start and the security light stays on, there is
a problem with the system. Turn the
ignition off and try again.
If the vehicle will not change ignition modes
(ACC/ACCESSORY, on, off), and the RKE
transmitter appears to be undamaged, try
another transmitter. Or, you may try placing
the transmitter in the transmitter pocket
located in the center console. See
Remote
Keyless Entry (RKE) System Operation (Key
Access) 010 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 013.
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) 010 or
Remote Keyless Entry (RKE) System
Operation (Keyless Access) 013
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.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
30 Keys, Doors, and Windows
It may be necessary to check the fuse. See
Fuses and Circuit Breakers0329. 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)07or
Keys (Keyless Access) 09. 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
(Continued)
Warning (Continued)
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's 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’s surface is curved so more can be
seen from the driver seat. The lower portion
is adjusted manually.
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.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Keys, Doors, and Windows 39
Press2to engage the rear window
lockout feature. The indicator light is on
when engaged.
Press
2again to disengage.
Windows Express Movement
All windows can be opened without holding
the window switch. Press the switch down
fully and quickly release to express open the
window.
If equipped, pull the window switch up fully
and quickly release to express close the
window.
Briefly press or pull the window switch in
the same direction to stop that window’s
express movement.
Express Window Down
L: If equipped, this button will be on the
center stack.
Press and hold
Lto open all windows.
Release
Lto stop all movement.
Use the power window switches to close
each window.
Window Automatic Reversal System
The express-close feature will reverse
window movement if it comes in contact
with an object. Extreme cold or ice could
cause the window to auto-reverse. The
window will operate normally after the
object or condition is removed.
Automatic Reversal System Override
{Warning
If automatic reversal system override is
active, the window will not reverse
automatically. You or others could be
injured and the window could be
damaged. Before using automatic reversal
system override, make sure that all
people and obstructions are clear of the
window path.
When the engine is on, override the
automatic reversal system by pulling and
holding the window switch if conditions
prevent it from closing.
Programming the Power Windows
Programming may be necessary if the
vehicle battery has been disconnected or
discharged. If the window is unable to
express-up, program each express-close
window: 1. Close all doors.
2. Turn the ignition on or to ACC/ ACCESSORY.
3. Partially open the window to be programmed. Then close it and continue
to pull the switch briefly after the
window has fully closed.
4. Open the window and continue to press the switch briefly after the window has
fully opened.
Remote Window Operation
If equipped, this feature allows the windows
to be opened remotely. If enabled in vehicle
personalization, press and hold
Kon the
RKE transmitter. See Vehicle Personalization
0 126.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Seats and Restraints 49
Obstructions
If something has blocked the driver seat
while recalling a memory position, the recall
may stop. Remove the obstruction and try
the recall again. If the memory position still
does not recall, see your dealer.
Heated and Ventilated Front
Seats
{Warning
If temperature change or pain to the skin
cannot be felt, the seat heater may cause
burns. To reduce the risk of burns, use
care when using the seat heater,
especially for long periods of time. Do
not place anything on the seat that
insulates against heat, such as a blanket,
cushion, cover, or similar item. This may
cause the seat heater to overheat. An
overheated seat heater may cause a burn
or may damage the seat.Heated and Ventilated Seat Buttons Shown,Heated Seat Buttons Similar
If equipped, the buttons are on the center
stack. To operate, the engine must be
running.
Press
Ior+to heat the driver or
passenger seatback only.
Press
Jorzto heat the driver or
passenger seat cushion and seatback.
Press
Cor{to ventilate the driver or
passenger seat.
The indicator light on the button comes on
when this feature is on. Press the button once for the highest
setting. With each press of the button, the
seat will change to the next lower setting,
and then to the off setting. The indicator
lights next to the buttons indicate three for
the highest setting and one for the lowest.
If the heated seats are on high for an
extended time, their level may automatically
be lowered.
Auto Heated Seats
When the vehicle is on, this feature will
automatically activate the heated seats at
the level required by the vehicle’s interior
temperature. The active high, medium, low,
or off heated seat level will be indicated by
the manual heated seat buttons on the
center stack. Use the manual heated seat
buttons on the center stack to turn auto
heated seats off. If the passenger seat is
unoccupied, the auto heated seats feature
will not activate that seat. The auto heated
seats feature can be programmed to always
be enabled when the vehicle is on. See
Vehicle Personalization
0126.
Remote Start Heated and Ventilated Seats
If equipped, the heated seats will turn on
automatically during a remote start if it is
cold outside and the ventilated seats will
turn on automatically if it is hot outside.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Seats and Restraints 51
{Warning
A seat belt that is improperly routed, not
properly attached, or twisted will not
provide the protection needed in a crash.
The person wearing the belt could be
seriously injured. After raising the rear
seatback, always check to be sure that
the seat belts are properly routed and
attached, and are not twisted.
Heated Rear Seats
{Warning
If you cannot feel temperature change or
pain to the skin, the seat heater may
cause burns. See the Warning under
Heated and Ventilated Front Seats049.
If available, the buttons are on the rear of
the center console. To operate, the engine
must be running.
Press
MorLto heat the left or right
outboard seat cushion. An indicator on the
climate control display appears when this
feature is on.
This feature turns on at the highest setting.
With each press of the button, the heated
seat changes to the next lower setting, and
then the off setting. Three lights indicate
the highest setting, and one light indicates
the lowest. If the heated seats are on high,
the level may automatically be lowered
after approximately 30 minutes.
Seat Belts
This section describes how to use seat belts
properly, and some things not to do.
{Warning
Do not let anyone ride where a seat belt
cannot be worn properly. In a crash,
if you or your passenger(s) are not
wearing seat belts, injuries can be much
worse than if you are wearing seat belts.
You can be seriously injured or killed by
hitting things inside the vehicle harder or
by being ejected from the vehicle. In
addition, anyone who is not buckled up
can strike other passengers in the vehicle.
It is extremely dangerous to ride in a
cargo area, inside or outside of a vehicle.
In a collision, passengers riding in these
areas are more likely to be seriously
injured or killed. Do not allow passengers
to ride in any area of the vehicle that is
not equipped with seats and seat belts.
Always wear a seat belt, and check that
all passenger(s) are restrained
properly too.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
62 Seats and Restraints
Warning (Continued)
vehicle should get out as soon as it is
safe to do so. If you have breathing
problems but cannot get out of the
vehicle after an airbag inflates, then get
fresh air by opening a window or a door.
If you experience breathing problems
following an airbag deployment, you
should seek medical attention.
The vehicle has a feature that may
automatically unlock the doors, turn on the
interior lamps and hazard warning flashers,
and shut off the fuel system after the
airbags inflate. The feature may also
activate, without airbag inflation, after an
event that exceeds a predetermined
threshold. After turning the ignition off and
then on again, the fuel system will return to
normal operation; the doors can be locked,
the interior lamps can be turned off, and
the hazard warning flashers can be turned
off using the controls for those features.
If any of these systems are damaged in the
crash they may not operate as normal.
{Warning
A crash severe enough to inflate the
airbags may have also damaged
important functions in the vehicle, such
as the fuel system, brake and steering
systems, etc. Even if the vehicle appears
to be drivable after a moderate crash,
there may be concealed damage that
could make it difficult to safely operate
the vehicle.
Use caution if you should attempt to
restart the engine after a crash has
occurred.
In many crashes severe enough to inflate
the airbag, windshields are broken by
vehicle deformation. Additional windshield
breakage may also occur from the front
outboard passenger airbag.
.Airbags are designed to inflate only once.
After an airbag inflates, you will need
some new parts for the airbag system.
If you do not get them, the airbag
system will not be there to help protect
you in another crash. A new system will
include airbag modules and possibly other
parts. The service manual for the vehicle
covers the need to replace other parts.
.The vehicle has a crash sensing and
diagnostic module which records
information after a crash. See Vehicle
Data Recording and Privacy 0410 and
Event Data Recorders 0411.
.Let only qualified technicians work on the
airbag systems. Improper service can
mean that an airbag system will not work
properly. See your dealer for service.
Passenger Sensing System
The vehicle has a passenger sensing system
for the front outboard passenger position.
The passenger airbag status indicator will
light on the overhead console when the
vehicle is started.
United States

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Instruments and Controls 95
Instruments and Controls
Controls
Steering Wheel Adjustment . . . . . . . . . . . . 96
Steering Wheel Controls . . . . . . . . . . . . . . . 96
Heated Steering Wheel . . . . . . . . . . . . . . . . . 96
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Windshield Wiper/Washer . . . . . . . . . . . . . . 97
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Power Outlets . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Wireless Charging . . . . . . . . . . . . . . . . . . . . . . 99
Warning Lights, Gauges, and Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . 102
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . 106
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Engine Oil Pressure Gauge . . . . . . . . . . . . . 107
Engine Coolant Temperature Gauge . . . 108
Voltmeter Gauge . . . . . . . . . . . . . . . . . . . . . . 109
Seat Belt Reminders . . . . . . . . . . . . . . . . . . . 109
Airbag Readiness Light . . . . . . . . . . . . . . . . . 110
Passenger Airbag Status Indicator . . . . . . 110
Charging System Light . . . . . . . . . . . . . . . . . 111 Malfunction Indicator Lamp (Check
Engine Light) . . . . . . . . . . . . . . . . . . . . . . . . . 111
Brake System Warning Light . . . . . . . . . . . 113
Electric Parking Brake Light . . . . . . . . . . . . 113
Service Electric Parking Brake Light . . . . . 113
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Four-Wheel-Drive Light . . . . . . . . . . . . . . . . . 114
Tow/Haul Mode Light . . . . . . . . . . . . . . . . . . 114
Hill Descent Control Light . . . . . . . . . . . . . . 114
Lane Departure Warning (LDW) Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Vehicle Ahead Indicator . . . . . . . . . . . . . . . . 115
Traction Off Light . . . . . . . . . . . . . . . . . . . . . . 115
Traction Control System (TCS)/Electronic Stability Control Light . . . . . . . . . . . . . . . . 115
Electronic Stability Control (ESC) Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Driver Mode Control Light . . . . . . . . . . . . . 117
Tire Pressure Light . . . . . . . . . . . . . . . . . . . . . 117
Engine Oil Pressure Light (Uplevel Cluster) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Low Fuel Warning Light . . . . . . . . . . . . . . . . 118
Security Light . . . . . . . . . . . . . . . . . . . . . . . . . . 118
High-Beam On Light . . . . . . . . . . . . . . . . . . . 118
Front Fog Lamp Light . . . . . . . . . . . . . . . . . . 118
Lamps On Reminder . . . . . . . . . . . . . . . . . . . 118
Cruise Control Light . . . . . . . . . . . . . . . . . . . . 119 Door Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . 119
Information Displays
Driver Information Center (DIC) (Base
Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Driver Information Center (DIC) (Midlevel and Uplevel) . . . . . . . . . . . . . . . 120
Head-Up Display (HUD) . . . . . . . . . . . . . . . . 123
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . . . . . . . . . . . 125
Engine Power Messages . . . . . . . . . . . . . . . 126
Vehicle Speed Messages . . . . . . . . . . . . . . . 126
Vehicle Personalization
Vehicle Personalization . . . . . . . . . . . . . . . . 126
Universal Remote System
Universal Remote System . . . . . . . . . . . . . . 131
Universal Remote System Programming . . . . . . . . . . . . . . . . . . . . . . . . . 131
Universal Remote System Operation . . . 133

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
102 Instruments and Controls
Warning Lights, Gauges, and
Indicators
Warning lights and gauges can signal that
something is wrong before it becomes
serious enough to cause an expensive repair
or replacement. Paying attention to the
warning lights and gauges could prevent
injury.
Some warning lights come on briefly when
the engine is started to indicate they are
working. When one of the warning lights
comes on and stays on while driving,
or when one of the gauges shows there
may be a problem, check the section that
explains what to do. Waiting to do repairs
can be costly and even dangerous.
Instrument Cluster
Base Cluster English Shown, Metric Similar
1.Tachometer 0106
2. Engine Oil Pressure Gauge 0107
3. Engine Coolant Temperature Gauge
0108
4. Fuel Gauge 0106
5. Voltmeter Gauge 0109
6. Speedometer 0106 7.
Driver Information Center (DIC) (Base
Level) 0119 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0120

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
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Instruments and Controls 103
Midlevel Cluster English Shown, Metric Similar
1.Tachometer 0106
2. Engine Oil Pressure Gauge 0107
3. Engine Coolant Temperature Gauge
0108
4. Fuel Gauge 0106
5. Voltmeter Gauge 0109
6. Speedometer 0106 7.
Driver Information Center (DIC) (Base
Level) 0119 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0120