2020 CHEVROLET SILVERADO check engine light

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
Driving and Operating 229
ABS performs a system check when
the vehicle is first driven.
A momentary motor or clicking noise
may be heard while this test is going
on, and the brake pedal may move
slightly. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
0 138.
ABS does not change the time
needed to get a foot on the brake
pedal and does not always
decrease stopping distance. If you
get too close to the vehicle ahead,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room ahead to stop,
even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly.
Hearing or feeling ABS operate is
normal.
Braking in Emergencies
ABS allows steering and braking at
the same time. In many
emergencies, steering can help
even more than braking.
Electric Parking Brake
The vehicle has an Electric Parking
Brake (EPB). The EPB can always
be activated, even if the ignition is off. To prevent draining the battery,
avoid repeated cycles of the EPB
when the engine is not running.
The system has a
Yor PARK
Electric Parking Brake light, and a
8
Service Parking Brake light. See
Electric Parking Brake Light 0137
and
Service Electric Parking Brake Light
0 138. There are also parking
brake-related Driver Information
Center (DIC) messages.
Before leaving the vehicle, check for
the
Yor PARK light to ensure that
the parking brake is applied.
EPB Apply
To apply the EPB:
1. Be sure the vehicle is at a complete stop.
2. Press the EPB switch momentarily.
The
Yor PARK light will flash and
then stay on once the EPB is fully
applied. If the
Yor PARK light
flashes continuously, then the EPB
is only partially applied or there is a

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
232 Driving and Operating
intended path. Trailer Sway Control
(TSC) is also on automatically when
the vehicle is started. SeeTrailer
Sway Control (TSC) 0304.
If cruise control is being used and
traction control or StabiliTrak/ESC
begins to limit wheel spin, cruise
control will disengage. Cruise
control may be turned back on when
road conditions allow.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
See If the Vehicle Is Stuck 0196
and “Turning the Systems Off and
On” later in this section.
When the transfer case (if equipped)
is in Four-Wheel Drive Low, the
stability system is automatically disabled,gcomes on, and the
appropriate message will appear on
the Driver Information Center (DIC).
Both traction control and StabiliTrak/
ESC are automatically disabled in
this condition.
The indicator light for both systems
is in the instrument cluster. This
light will:
. Flash when TCS is limiting
wheel spin.
. Flash when StabiliTrak/ESC is
activated.
. Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.
If
dcomes on and stays on:
1. Stop the vehicle.
2. Turn the engine off and wait 15 seconds.
3. Start the engine.
Drive the vehicle. If
dcomes on and
stays on, the vehicle may need
more time to diagnose the problem.
If the condition persists, see your
dealer.
Turning the Systems Off
and On
The button for TCS and StabiliTrak/
ESC is on the center stack.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
282 Driving and Operating
{Warning
If a fire starts while you are
refueling, do not remove the fill
nozzle. Shut off the flow of fuel by
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Caution
If a new fuel cap is needed, get
the right type of cap from your
dealer. The wrong type of fuel cap
may not fit properly, may turn on
the malfunction indicator lamp,
and could damage the fuel
system and emissions system.
SeeMalfunction Indicator Lamp
(Check Engine Light) 0135.
Filling a Portable Fuel
Container
{Warning
Never fill a portable fuel container
while it is in the vehicle. Static
electricity discharge from the
container can ignite the fuel
vapor. You or others could be
badly burned and the vehicle
could be damaged. To help avoid
injury to you and others:
. Dispense fuel only into
approved containers.
. Do not fill a container while
it is inside a vehicle, in a
vehicle's trunk, in a pickup
bed, or on any surface other
than the ground.
. Bring the fill nozzle in
contact with the inside of
the fill opening before
operating the nozzle.
Maintain contact until filling
is complete.
(Continued)
Warning (Continued)
.Keep sparks, flames, and
smoking materials away
from fuel.
. Do not use electronic
devices while pumping fuel.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
300 Driving and Operating
Trailer Lamps
Always check that all trailer lamps
are working at the beginning of each
trip, and periodically on longer trips.
If equipped, the Trailering App will
monitor the RH turn/brake lamp
circuit, LH turn/brake lamp circuit,
running lamp circuit, and reverse
lamp circuits on the trailer. DIC
messages and Trailering App alerts
may be displayed if lighting circuit
issues are detected on the trailer.
Pressing START LIGHT TEST in the
Trailering App automatically
activates the trailer lamps. The
Trailering App is not a substitute for
manually inspecting your trailer
lamps. SeeTrailering App 0306.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing
lanes, or stopping. When towing a
trailer, the arrows on the instrument
cluster will illuminate even if the
trailer is not properly connected or
the bulbs are burned out.
Tow/Haul Mode
For instructions on how to enter
Tow/Haul Mode, see Driver Mode
Control 0234.
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. See Tow/Haul Mode 0223.
Tow/Haul Mode is designed to be
most effective when the vehicle and
trailer combined weight is at least
75% of the vehicle's Gross
Combined Weight Rating (GCWR).
See “Trailer Weight ”under Trailer
Towing 0288.
Tow/Haul Mode is most useful when
towing a heavy trailer or carrying a
large or heavy load:
. Through rolling terrain.
. In stop-and-go traffic.
. In busy parking lots.
Operating the vehicle in Tow/Haul
Mode when lightly loaded or not
towing will not cause damage;
however, it is not recommended and
may result in unpleasant engine and transmission driving characteristics,
heavy or light steering efforts, and
reduced fuel economy.
Integrated Trailer Brake
Control System
The vehicle may have an Integrated
Trailer Brake Control (ITBC) system
for use with electric trailer brakes or
most electric over hydraulic trailer
brake systems. These instructions
apply to both types of electric trailer
brakes.
This symbol is on the Trailer Brake
Control Panel on vehicles with an
ITBC system. The power output to
the trailer brakes is proportional to
the amount of vehicle braking. This
available power output to the trailer
brakes can be adjusted to a wide
range of trailering situations.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
304 Driving and Operating
4. If the CHECK TRAILERWIRING message reappears,
the electrical fault is on the
vehicle side.
If the CHECK TRAILER WIRING
message only reappears when
connecting the trailer wiring harness
to the vehicle, the electrical fault is
on the trailer side.
SERVICE TRAILER BRAKE
SYSTEM: This message will display
when there is a problem with the
ITBC system. If this message
continues over multiple ignition
cycles, have the vehicle serviced.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message displays
while driving, the ITBC system may
not be fully functional or may not
function at all. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service. A GM dealer may be able to
diagnose and repair problems with
the trailer. However, any diagnosis
and repair of the trailer is not
covered under the vehicle warranty.
Contact your trailer dealer for
assistance with trailer repairs and
trailer warranty information.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak/Electronic
Stability Control (ESC) have a
Trailer Sway Control (TSC) feature.
Trailer sway is unintended
side-to-side motion of a trailer while
towing. If the vehicle is towing a
trailer and the TSC detects that
sway is increasing, the vehicle
brakes are selectively applied at
each wheel, to help reduce
excessive trailer sway. If equipped
with the Integrated Trailer Brake
Control (ITBC) system, and the
trailer has an electric brake system,
StabiliTrak/ESC may also apply the
trailer brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak/
ESC warning light will flash on the
instrument cluster. Reduce vehicle
speed by gradually removing your
foot from the accelerator. If trailer
sway continues, StabiliTrak/ESC
can reduce engine torque to help
slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned
off. See
Traction Control/Electronic
Stability Control 0231.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
318 Driving and Operating
This setting will default to OFF for
each Trailer Profile, including the
Guest Trailer Profile.
If Tow/Haul Mode is off and this
setting is on for a Trailer Profile,
each time the ignition is turned on a
reminder will appear to turn on Tow/
Haul Mode when the Trailer Profile
is active.
If Tow/Haul Mode is on and this
setting is on for a Trailer Profile, the
reminder will not appear when the
Trailer Profile is active.Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC)
is used for vehicle service and
Emission Inspection/
Maintenance testing. See
Malfunction Indicator Lamp
(Check Engine Light)0135.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 080 and
Adding Equipment to the
Airbag-Equipped Vehicle 080.
For information on wiring auxiliary
switches, see www.gmupfitter.com
or contact your dealer.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
Vehicle Care 323
Vehicle Care
General Information
General Information . . . . . . . . . . 324
California Proposition65 Warning . . . . . . . . . . . . . . . . . 325
California Perchlorate Materials Requirements . . . . . 325
Accessories and Modifications . . . . . . . . . . . . . . . . 325
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 326
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 326
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 328
Engine Oil . . . . . . . . . . . . . . . . . . . . 335
Engine Oil Life System . . . . . . . 337
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 339
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 339
Engine Air Cleaner/Filter . . . . . . 340
Cooling System . . . . . . . . . . . . . . 342
Engine Overheating . . . . . . . . . . 347
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . 348
Engine Fan . . . . . . . . . . . . . . . . . . . 349 Power Steering Fluid . . . . . . . . . 350
Washer Fluid . . . . . . . . . . . . . . . . . 350
Brakes . . . . . . . . . . . . . . . . . . . . . . . 351
Brake Pad Life System . . . . . . . 352
Brake Fluid . . . . . . . . . . . . . . . . . . . 353
Battery - North America . . . . . . 354
Four-Wheel Drive . . . . . . . . . . . . . 356
Front Axle . . . . . . . . . . . . . . . . . . . . 357
Rear Axle . . . . . . . . . . . . . . . . . . . . 357
Noise Control System . . . . . . . . 357
Starter Switch Check . . . . . . . . . 358
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 359
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 359
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 359
Wiper Blade Replacement . . . . 360
Glass Replacement . . . . . . . . . . 361
Windshield Replacement . . . . . 361
Gas Strut(s) . . . . . . . . . . . . . . . . . . 361
Headlamp Aiming
Front Headlamp Aiming . . . . . . 362
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 362
Halogen Bulbs . . . . . . . . . . . . . . . . 362
LED Lighting . . . . . . . . . . . . . . . . . 363 Headlamps, Front Turn Signal,
Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 363
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 364
Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 365
License Plate Lamp . . . . . . . . . . 366
Electrical System
Electrical System Overload . . . 366
Fuses and Circuit Breakers . . . 366
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 367
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 370
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 372
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 375
All-Season Tires . . . . . . . . . . . . . . 375
Winter Tires . . . . . . . . . . . . . . . . . . 376
Low-Profile Tires . . . . . . . . . . . . . 376
All-Terrain Tires . . . . . . . . . . . . . . . 377
Tire Sidewall Labeling . . . . . . . . 377
Tire Designations . . . . . . . . . . . . . 379
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 381

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
418 Vehicle Care
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
0328.
{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,
(Continued)
Warning (Continued)
and some have been blinded.
Use a flashlight if you need more
light.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
your eyes or on your skin, flush
the place with water and get
medical help immediately.
{Warning
Fans or other moving engine
parts can injure you badly. Keep
your hands away from moving
parts once the engine is running.
6. Check that the jumper cables do not have loose or missing
insulation. If they do, you could
get a shock. The vehicles
could be damaged too. Before you connect the cables,
here are some basic things you
should know. Positive (+) will
go to positive (+) or to a remote
positive (+) terminal if the
vehicle has one. Negative (−)
will go to a heavy, unpainted
metal engine part or to a
remote negative (−) terminal if
the vehicle has one.
Do not connect positive (+) to
negative (−) or you will get a
short that would damage the
battery and maybe other parts
too. And do not connect the
negative (−) cable to the
negative (−) terminal on the
dead battery because this can
cause sparks.
7. Connect one end of the red positive (+) cable to the remote
positive (+) terminal of the
vehicle with the discharged
battery.
8. Do not let the other end touch metal. Connect it to the
positive (+) terminal of the