ignition CHEVROLET SILVERADO 2500HD 2021 Manual Online

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Vehicle Care 357
2. Turn the wing nut counterclockwise toremove the wheel blocks and the wheel
block retainer.
3. Turn the wing nut used to retain the storage bag and tools counterclockwise
to remove it.
Use the jack handle extensions and the
wheel wrench to remove the
underbody-mounted spare tire.
1. Spare Tire (Valve Stem Pointed Down)
2. Tire/Wheel Retainer
3. Hoist Cable
4. Hoist Assembly
5. Hoist Shaft
6. Jack Handle Extensions 7. Wheel Wrench
8. Spare Tire Lock (If Equipped)
9. Hoist Shaft Access Hole
10. Hoist End of Extension Tool
1. Open the spare tire lock cover on the
bumper and use the ignition key to
remove the spare tire lock (8). To remove
the spare tire lock, insert the ignition
key, turn, and pull straight out.
2. Assemble the wheel wrench (7) and thetwo jack handle extensions (6), as shown.
Spare Tire Cable (If Equipped)
3. If the vehicle is equipped with a spare tire cable disconnect the cable from the
attachment on the frame by unclipping
it from the frame attachment bracket.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
368 Vehicle Care
1. Check the other vehicle. It must have a12-volt battery with a negative ground
system.
Caution
If the other vehicle does not have a
12-volt system with a negative ground,
both vehicles can be damaged. Only use
a vehicle that has a 12-volt system with a
negative ground for jump starting.
2. If you have a vehicle with a diesel engine with two batteries, you should
know before you begin that, especially in
cold weather, you may not be able to
get enough power from a single battery
in another vehicle to start your diesel
engine. If your vehicle has more than
one battery, using the battery that is
closer to the starter will reduce electrical
resistance. This is located on the
passenger side, in the rear of the engine
compartment.
3. Get the vehicles close enough so the jumper cables can reach, but be sure the
vehicles are not touching each other.
If they are, it could cause an unwanted
ground connection. You would not be able to start your vehicle, and the bad
grounding could damage the electrical
systems.
To avoid the possibility of the vehicles
rolling, set the parking brake firmly on
both vehicles involved in the jump start
procedure. Put the automatic
transmission in P (Park) before setting
the parking brake. If you have a
four-wheel-drive vehicle, be sure the
transfer case is in a drive gear, not in
N (Neutral).
Caution
If any accessories are left on or plugged
in during the jump starting procedure,
they could be damaged. The repairs
would not be covered by the vehicle
warranty. Whenever possible, turn off or
unplug all accessories on either vehicle
when jump starting.
4. Turn the ignition off on both vehicles. Unplug unnecessary accessories plugged
into the accessory power outlets. Turn
off the radio and all the lamps that are
not needed. This will avoid sparks and
help save both batteries. And it could
save the radio! 5. Open the hood on the other vehicle and
locate the positive (+) and negative (−)
terminal locations on that vehicle.
The positive (+) terminal is under a red
plastic cover at the positive battery post.
To uncover the positive (+) terminal,
open the red plastic cover.
For more information on the location of
the remote positive (+) and remote
negative (−) terminals, see Engine
Compartment Overview 0304.
{Warning
An electric fan can start up even when
the engine is not running and can injure
you. Keep hands, clothing, and tools
away from any underhood electric fan.
{Warning
Using a match near a battery can cause
battery gas to explode. People have been
hurt doing this, and some have been
blinded. Use a flashlight if you need
more light.
(Continued)

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
372 Vehicle Care
the transmission to D (Drive) and then to
R (Reverse). There should be no
movement while shifting the
transmission.
6. Shift the transmission to D (Drive).
7. If equipped with an ignition key, turn the ignition to ACC/ACCESSORY.
If equipped with Keyless Access, turn the
engine off. Disregard the Shift to P (Park)
DIC message. See Ignition Positions
(Keyless Access) 0226 or
Ignition Positions (Key Access) 0224.
{Warning
To avoid death, serious injury,
or property damage, before dinghy
towing the vehicle, always disconnect and
secure the negative battery cable and
cover the negative battery post and cable
with a non-conductive material. If the
battery is left connected or the battery
cable contacts the post, the Electric
Parking Brake may activate during
towing, which could cause a crash.
8. Disconnect the negative (–) battery cable. See “Negative Battery Cable
Disconnection” inBattery - North
America 0318. 9. Shift the transmission to P (Park).
Caution
If the steering column is locked, vehicle
damage may occur.
10. Move the steering wheel to make sure the steering column is unlocked.
11. If the vehicle has an ignition key, keep it in the towed vehicle in ACC/ACCESSORY
to prevent the steering column from
locking. If the vehicle is equipped with
Keyless Access, keep the RKE transmitter
outside of the vehicle and manually lock
the doors. Access the vehicle by using
the key in the door lock. See Door Locks
0 21.
Disconnecting the Towed Vehicle
Before disconnecting from the tow vehicle: 1. Park on a level surface. Secure the vehicle with wheel blocks.
2. Re-connect the negative (–) battery. See Battery - North America 0318.
3. Turn on the ignition with the engine off. For vehicles with a key, turn the ignition
to ON/RUN with the engine off. If the
vehicle is equipped with Keyless Access,
with your foot off the brake pedal, press and hold ENGINE START/STOP for
five seconds until the green light comes
on in the button. See
Ignition Positions
(Keyless Access) 0226 or
Ignition Positions (Key Access) 0224.
4. Set the parking brake. See Electric
Parking Brake 0240.
5. Disconnect from the tow vehicle.
6. Shift the transmission to N (Neutral).
7. Shift the transfer case to 2
m(Two-Wheel
Drive High). When the shift to 2
m
(Two-Wheel Drive High) is complete, the
light in the instrument cluster will stop
flashing and stay lit. See
Four-Wheel-Drive Light 0114.
8. Start the engine. Check that the vehicle is in 2
m(Two-Wheel Drive High) by
starting the engine and shifting the
transmission to D (Drive) and then to
R (Reverse). There should be movement
of the vehicle while shifting.
9. Shift the transmission to P (Park) and turn off the ignition.
10. Release the parking brake and remove the wheel blocks.
11. Reset any lost presets.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
386 Service and Maintenance
.Check restraint system components. See
Safety System Check056.
.Visually inspect fuel system for damage
or leaks.
.Visually inspect exhaust system and
nearby heat shields for loose or damaged
parts.
.Lubricate body components. See Exterior
Care 0373.
.Check starter switch. See Starter Switch
Check 0321.
.Check automatic transmission shift lock
control function. See Automatic
Transmission Shift Lock Control Function
Check 0322.
.Check ignition transmission lock. See
Ignition Transmission Lock Check 0322.
.Check parking brake and automatic
transmission park mechanism. See Park
Brake and P (Park) Mechanism Check
0 322.
.Check accelerator pedal for damage, high
effort, or binding. Replace if needed.
.Visually inspect gas strut for signs of
wear, cracks, or other damage. Check the
hold open ability of the strut. If the hold
open is low, service the gas strut. See Gas
Strut(s) 0323.
.Inspect sunroof track and seal,
if equipped. See Sunroof040.
.Verify spare tire key lock operation and
lubricate as needed. See Tire Changing
0 356.
.Visually inspect the spare tire to ensure
that it is tightly stowed under the vehicle.
Push, pull, and try to turn the tire. If the
spare tire moves, tighten as necessary.
See Tire Changing 0356.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
OnStar 413
.Receive a Diagnostic check of the vehicle's
key operating systems.
.Receive Roadside Assistance.
.Manage Wi-Fi Settings, if equipped.
Press
>to get a priority connection to an
OnStar Advisor available 24/7 to:
.Get help for an emergency.
.Be a Good Samaritan or respond to an
AMBER Alert.
.Get assistance in severe weather or other
crisis situations and find evacuation
routes.
OnStar Services
Emergency
Emergency Services require an active safety
and security plan. With Automatic Crash
Response, built-in sensors can automatically
alert a specially trained OnStar Advisor who
is immediately connected in to the vehicle
to help.
Press
>for a priority connection to an
OnStar Advisor who can contact emergency
service providers, direct them to your exact
location, and relay important information. With OnStar Crisis Assist, specially trained
Advisors are available 24 hours a day, 7 days
a week, to provide a central point of
contact, assistance, and information during a
crisis.
With Roadside Assistance, Advisors can
locate a nearby service provider to help with
a flat tire, a battery jump, or an empty
gas tank.
Security
If equipped, OnStar provides these services:
.With Stolen Vehicle Assistance, OnStar
Advisors can use GPS to pinpoint the
vehicle and help authorities quickly
recover it.
.With Remote Ignition Block, if equipped,
OnStar can block the engine from being
restarted.
.With Stolen Vehicle Slowdown,
if equipped, OnStar can work with law
enforcement to gradually slow the
vehicle down.
Theft Alarm Notification
If equipped, if the doors are locked and the
vehicle alarm sounds, a notification by text,
e-mail, or phone call will be sent. If the
vehicle is stolen, an OnStar Advisor can work
with authorities to recover the vehicle.
OnStar Additional
Information
In-Vehicle Audio Messages
Audio messages may play important
information at the following times:
.Prior to vehicle purchase. PressQto
set up an account.
.After change in ownership and at
90 days.
Transferring Service
PressQto request account transfer
eligibility information. The Advisor can
cancel or change account information.
Selling/Transferring the Vehicle
Call 1-888-4ONSTAR (1-888-466-7827)
immediately to terminate your OnStar or
connected services if the vehicle is disposed
of, sold, transferred, or if the lease ends.

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
OnStar 415
Languages
The vehicle can be programmed to respond
in multiple languages. Press
Qand ask for
an Advisor. Advisors are available in English,
Spanish, and French. Available languages
may vary by country.
Potential Issues
OnStar cannot perform Remote Door Unlock
or Stolen Vehicle Assistance after the vehicle
has been off continuously for 10 days
without an ignition cycle. If the vehicle has
not been started for 10 days, OnStar can
contact Roadside Assistance or a locksmith
to help gain access to the vehicle.
Global Positioning System (GPS)
.Obstruction of the GPS can occur in a
large city with tall buildings; in parking
garages; around airports; in tunnels and
underpasses; or in an area with very
dense trees. If GPS signals are not
available, the OnStar system should still
operate to call OnStar. However, OnStar
could have difficulty identifying the exact
location.
.In emergency situations, OnStar can use
the last stored GPS location to send to
emergency responders. A temporary loss of GPS can cause loss of
the ability to send a Turn-by-Turn
Navigation route. The Advisor may give a
verbal route or may ask for a call back after
the vehicle is driven into an open area.
Cellular and GPS Antennas
Cellular reception is required for OnStar to
send remote signals to the vehicle. Do not
place items over or near the antenna to
prevent blocking cellular and GPS signal
reception.
Unable to Connect to OnStar Message
If there is limited cellular coverage or the
cellular network has reached maximum
capacity, this message may come on. Press
Qto try the call again or try again after
driving a few miles into another
cellular area.
Vehicle and Power Issues
OnStar services require a vehicle electrical
system, wireless service, and GPS satellite
technologies to be available and operating
for features to function properly. These
systems may not operate if the battery is
discharged or disconnected.
Add-on Electrical Equipment
The OnStar system is integrated into the
electrical architecture of the vehicle. Do not
add any electrical equipment. See Add-On
Electrical Equipment 0297. Added electrical
equipment may interfere with the operation
of the OnStar system and cause it to not
operate.
Vehicle Software Updates
OnStar or GM may remotely deliver
software updates or changes to the vehicle
without further notice or consent. These
updates or changes may enhance or
maintain safety, security, or the operation
of the vehicle or the vehicle systems.
Software updates or changes may affect or
erase data or settings that are stored in the
vehicle, such as saved navigation
destinations or pre-set radio stations.
Neither OnStar nor GM is responsible for
any affected or erased data or settings.
These updates or changes may also collect
personal information. Such collection is
described in the OnStar privacy statement or
separately disclosed at the time of
installation. These updates or changes may
also cause a system to automatically
communicate with GM servers to collect
information about vehicle system status,

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
422 Index
Check (cont'd)Ignition Transmission Lock . . . . . . . . . . . . . 322
Child Restraints Infants and Young Children . . . . . . . . . . . . . 69
Lower Anchors and Tethers forChildren . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Older Children . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Securing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84, 87
Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Cleaning Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 373
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Climate Control Systems . . . . . . . . . . . . . . . . . 199 Air Conditioning . . . . . . . . . . . . . . . . . . . . . . . 199
Dual Automatic . . . . . . . . . . . . . . . . . . . . . . . . 201
Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Cluster, Instrument . . . . . . . . . . . . . . . . . . . . . . 102
Collision Damage Repair . . . . . . . . . . . . . . . . . 407
Compartments Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Connected Services Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417 Connections
Connected Services . . . . . . . . . . . . . . . . . . . . 418
Control Hill Descent . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Traction and Electronic Stability . . . . . . . 242
Control Light Hill Descent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Control of a Vehicle . . . . . . . . . . . . . . . . . . . . . 208
Controls Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . 146
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Coolant
Engine Temperature Gauge . . . . . . . . . . . . 108
Engine Temperature Warning Light . . . . . 116
Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199, 201
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Courtesy Transportation Program . . . . . . . . 406
Coverage Explanations . . . . . . . . . . . . . . . . . . . 170
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . 246 Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Cupholders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Customer Assistance . . . . . . . . . . . . . . . . . . . . . 403
Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Text Telephone (TTY) Users . . . . . . . . . . . . 403
Customer Information
Publications Ordering Information . . . . . 408
Customer Satisfaction Procedure . . . . . . . . . 401
Cybersecurity . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410D
Damage Repair, Collision . . . . . . . . . . . . . . . . . 407
Danger, Warning, and Caution . . . . . . . . . . . . . .2
Data Collection Infotainment System . . . . . . . . . . . . . . . . . . . 411
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Data Recorders, Event . . . . . . . . . . . . . . . . . . . . 411
Database Coverage Explanations . . . . . . . . . 170
Daytime Running Lamps (DRL) . . . . . . . . . . . 136
Defensive Driving . . . . . . . . . . . . . . . . . . . . . . . . 208
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Destination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Diagnostics Connected Services . . . . . . . . . . . . . . . . . . . . 419
Differential, Limited-Slip . . . . . . . . . . . . . . . . . 245
Distracted Driving . . . . . . . . . . . . . . . . . . . . . . . . 207
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . 22
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Power Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Drive Belt Routing, Engine . . . . . . . . . . . . . . .400
Driver Teen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Driver Assistance Systems . . . . . . . . . . . . . . . 247
Driver Information Center (DIC) . . . . . . 119, 120
Driver Mode Control . . . . . . . . . . . . . . . . . . . . . 244

Chevrolet Silverado 2500 HD/3500 HD Owner Manual (GMNA-Localizing-U.
S./Canada/Mexico-14632154) - 2021 - CRC - 11/20/20
Index 425
Hill Descent Control Light . . . . . . . . . . . . . . . . . 114
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . . . . 242
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
How to Wear Seat Belts Properly . . . . . . . . . .52
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .199, 201
I
If the System Needs Service . . . . . . . . . . . . . 170
Ignition Positions . . . . . . . . . . . . . . . . . . . 224, 226
Ignition Transmission Lock Check . . . . . . . . 322
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
IndicatorVehicle Ahead . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Infants and Young Children, Restraints . . . . 69
Information Publication Ordering . . . . . . . . . . . . . . . . . . . 408
Infotainment System . . . . . . . . . . . . . . . . . . . . . 411
Instrument Cluster . . . . . . . . . . . . . . . . . . . . . . . 102
Instrument Panel Overview . . . . . . . . . . . . . . . . 4
Interior Rearview Mirrors . . . . . . . . . . . . . . . . . 34
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 1, 143
J
Jack Auxiliary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Jump Starting - North America . . . . . . . . . . . 367
K
Keyless Entry
Remote (RKE) System . . . . . . . . . . . . . . . . 10, 13
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7, 9
L
Labeling, Tire Sidewall . . . . . . . . . . . . . . . . . . . 338
Lamps Auxiliary Roof Mounted Lamp . . . . . . . . . 139
Daytime Running (DRL) . . . . . . . . . . . . . . . . 136
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Exterior Cargo . . . . . . . . . . . . . . . . . . . . . . . . . 139
Exterior Controls . . . . . . . . . . . . . . . . . . . . . . . 134
Exterior Lamps Off Reminder . . . . . . . . . . 136
Exterior Lighting Battery Saver . . . . . . . . 142
License Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Malfunction Indicator (CheckEngine) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
On Reminder . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Lane Change Alert (LCA) . . . . . . . . . . . . . . . . . 261
Lane Departure Warning (LDW) . . . . . . . . . . 262
Lane Departure Warning Light . . . . . . . . . . . . 115
Lap-Shoulder Belt . . . . . . . . . . . . . . . . . . . . . . . . . 54
LATCH System Replacing Parts after a Crash . . . . . . . . . . . 84
LATCH, Lower Anchors and Tethers for Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Lighting
Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Illumination Control . . . . . . . . . . . . . . . . . . . 140
LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Task . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Lights Airbag Readiness . . . . . . . . . . . . . . . . . . . . . . 110
Antilock Brake System (ABS)Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Brake System Warning . . . . . . . . . . . . . . . . . 113
Charging System . . . . . . . . . . . . . . . . . . . . . . . 111
Check Engine (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Door Ajar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Driver Mode Control . . . . . . . . . . . . . . . . . . . . 117
Electric Parking Brake . . . . . . . . . . . . . . . . . . . 113
Electronic Stability Control (ESC), Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Coolant Temperature Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Engine Oil Pressure . . . . . . . . . . . . . . . . . . . . . 117
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Four-Wheel-Drive . . . . . . . . . . . . . . . . . . . . . . . 114
Front Fog Lamp . . . . . . . . . . . . . . . . . . . . . . . . . 118
High-Beam On . . . . . . . . . . . . . . . . . . . . . . . . . . 118