warning light CHEVROLET SUBURBAN 2020 Workshop Manual

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
Vehicle Care 283
Vehicle Care
General Information
General Information . . . . . . . . . . 284
California Proposition65 Warning . . . . . . . . . . . . . . . . . 285
California Perchlorate Materials Requirements . . . . . 285
Accessories and Modifications . . . . . . . . . . . . . . . . 285
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 286
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 286
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 288
Engine Oil . . . . . . . . . . . . . . . . . . . . 293
Engine Oil Life System . . . . . . . 295
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 296
Automatic Transmission Fluid (10-Speed Transmission) . . . 299
Engine Air Cleaner/Filter . . . . . . 300
Cooling System . . . . . . . . . . . . . . 301
Engine Overheating . . . . . . . . . . 305
Engine Fan . . . . . . . . . . . . . . . . . . . 306
Washer Fluid . . . . . . . . . . . . . . . . . 306
Brakes . . . . . . . . . . . . . . . . . . . . . . . 307 Brake Fluid . . . . . . . . . . . . . . . . . . . 308
Battery - North America . . . . . . 309
Four-Wheel Drive . . . . . . . . . . . . . 310
Front Axle . . . . . . . . . . . . . . . . . . . . 310
Rear Axle . . . . . . . . . . . . . . . . . . . . . 311
Starter Switch Check . . . . . . . . . 311
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 311
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 311
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 312
Wiper Blade Replacement . . . . 312
Glass Replacement . . . . . . . . . . 313
Windshield Replacement . . . . . 313
Gas Strut(s) . . . . . . . . . . . . . . . . . . 314
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 315
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 315
Halogen Bulbs . . . . . . . . . . . . . . . . 315
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 315
LED Lighting . . . . . . . . . . . . . . . . . 315
Headlamps . . . . . . . . . . . . . . . . . . . 316
Fog Lamps . . . . . . . . . . . . . . . . . . . 316
Front Turn Signal Lamps . . . . . 316 Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 317
License Plate Lamp . . . . . . . . . . 318
Electrical System
Electrical System Overload . . . 319
Fuses and Circuit Breakers . . . 319
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 320
Instrument Panel Fuse Block (Left) . . . . . . . . . . . . . . . . . 324
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 327
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 329
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 330
All-Season Tires . . . . . . . . . . . . . . 331
Winter Tires . . . . . . . . . . . . . . . . . . 331
Low-Profile Tires . . . . . . . . . . . . . 332
All-Terrain Tires . . . . . . . . . . . . . . . 332
Tire Sidewall Labeling . . . . . . . . 332
Tire Designations . . . . . . . . . . . . . 333
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 334
Tire Pressure . . . . . . . . . . . . . . . . . 337
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 338

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
308 Vehicle Care
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications. SeeCapacities and
Specifications 0397.
Brake pads should be replaced as
complete sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service may be required.
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement
parts. If this is not done, the brakes
may not work properly. The braking
performance expected can change in many other ways if the wrong
replacement brake parts are
installed or if parts are improperly
installed.
Brake Fluid
The brake master cylinder reservoir
is filled with GM approved DOT 3
brake fluid as indicated on the
reservoir cap. See
Engine
Compartment Overview 0288 for
the location of the reservoir.
Checking Brake Fluid
With the vehicle in P (Park) on a
level surface, the brake fluid level
should be between the minimum
and maximum marks on the brake
fluid reservoir.
There are only two reasons why the
brake fluid level in the reservoir may
go down: .
Normal brake lining wear. When
new linings are installed, the
fluid level goes back up.
. A fluid leak in the brake
hydraulic system. Have the
brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid
reservoir cap and the area around
the cap before removing it.
Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are
installed. Add or remove fluid, as
necessary, only when work is done
on the brake hydraulic system.
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged. (Continued)

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
Vehicle Care 309
Warning (Continued)
Add brake fluid only when work is
done on the brake hydraulic
system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light 0139.
Brake fluid absorbs water over time
which degrades the effectiveness of
the brake fluid. Replace brake fluid
at the specified intervals to prevent
increased stopping distance. See
Maintenance Schedule 0383.
What to Add
Use only GM approved DOT 3
brake fluid from a clean, sealed
container. See Recommended
Fluids and Lubricants 0392.
{Warning
The wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.
Caution
If brake fluid is spilled on the
vehicle's painted surfaces, the
paint finish can be damaged.
Immediately wash off any painted
surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove
the cap and do not add fluid.
Refer to the replacement number
shown on the original battery label
when a new battery is needed. See
Engine Compartment Overview
0288 for battery location.
{Warning
WARNING: Battery posts,
terminals, and related
accessories contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Batteries also
contain other chemicals known to
the State of California to cause
cancer. WASH HANDS AFTER
HANDLING. For more information
go to www.P65Warnings.ca.gov/
passenger-vehicle.
See California Proposition
65 Warning 0285 and the back
cover.
Vehicle Storage
{Warning
Batteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
(Continued)

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
Vehicle Care 315
Headlamp Aiming
Headlamp aim has been preset and
should need no further adjustment.
If the vehicle is damaged in a crash,
the headlamp aim may be affected.
If adjustment to the headlamps is
necessary, see your dealer.
Bulb Replacement
For the proper type of replacement
bulbs, or any bulb changing
procedure not listed in this section,
contact your dealer.
Caution
Do not replace incandescent
bulbs with aftermarket LED
replacement bulbs. This can
cause damage to the vehicle
electrical system.
Halogen Bulbs
{Warning
Halogen bulbs have pressurized
gas inside and can burst if you
drop or scratch the bulb. You or
others could be injured. Be sure
to read and follow the instructions
on the bulb package.
High Intensity Discharge
(HID) Lighting
{Warning
The High Intensity Discharge
(HID) lighting system operates at
a very high voltage. If you try to
service any of the system
components, you could be
seriously injured. Have your
dealer or a qualified technician
service them.
After an HID headlamp bulb has
been replaced, the beam might be a
slightly different shade than it was
originally. This is normal.
LED Lighting
This vehicle has several LED lamps.
For replacement of any LED lighting
assembly, contact your dealer.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
340 Vehicle Care
Tire Pressure Monitor
Operation
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS is designed to warn the
driver when a low tire pressure
condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire
and wheel assembly. The TPMS
sensors monitor the air pressure in
the tires and transmit the tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning light
located on the instrument cluster.
If the warning light comes on, stop
as soon as possible and inflate the
tires to the recommended pressureshown on the Tire and Loading
Information label. See
Vehicle Load
Limits 0200.
A message to check the pressure in
a specific tire displays in the Driver
Information Center (DIC). The low
tire pressure warning light and the
DIC warning message come on at
each ignition cycle until the tires are
inflated to the correct inflation
pressure. If the vehicle has DIC
buttons, tire pressure levels can be
viewed. For additional information
and details about the DIC operation
and displays, see Driver Information
Center (DIC) (Base Level) 0145 or
Driver Information Center (DIC)
(Uplevel) 0147.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the
air pressure is getting low and
needs to be inflated to the proper
pressure.
A Tire and Loading Information label
shows the size of the original
equipment tires and the correct inflation pressure for the tires when
they are cold. See
Vehicle Load
Limits 0200, for an example of the
Tire and Loading Information label
and its location. Also see Tire
Pressure 0337.
The TPMS can warn about a low
tire pressure condition but it does
not replace normal tire
maintenance. See Tire Inspection
0 344, Tire Rotation 0344 and
Tires 0330.
Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use only
the GM approved tire sealant
available through your dealer or
included in the vehicle.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
Vehicle Care 341
TPMS Malfunction Light and
Message
The TPMS will not function properly
if one or more of the TPMS sensors
are missing or inoperable. When the
system detects a malfunction, the
low tire pressure warning light
flashes for about one minute and
then stays on for the remainder of
the ignition cycle. A DIC warning
message also displays. The
malfunction light and DIC warning
message come on at each ignition
cycle until the problem is corrected.
Some of the conditions that can
cause these to come on are:
.One of the road tires has been
replaced with the spare tire. The
spare tire does not have a
TPMS sensor. The malfunction
light and the DIC message
should go off after the road tire
is replaced and the sensor
matching process is performed
successfully. See "TPMS Sensor
Matching Process" later in this
section. .
The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The
malfunction light and the DIC
message should go off after
successfully completing the
sensor matching process. See
"TPMS Sensor Matching
Process" later in this section.
. One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and
the sensor matching process is
performed successfully. See
your dealer for service.
. Replacement tires or wheels do
not match the original equipment
tires or wheels. Tires and wheels
other than those recommended
could prevent the TPMS from
functioning properly. See Buying
New Tires 0346. .
Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly, it cannot detect or signal a
low tire pressure condition. See
your dealer for service if the TPMS
malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure.
When the low tire pressure warning
light comes on:
1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal
lamp will flash.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
342 Vehicle Care
When the recommended
pressure is reached, the horn
sounds once and the turn
signal lamp will stop flashing
and briefly turn solid.
Repeat these steps for all
underinflated tires that have
illuminated the low tire pressure
warning light.
{Warning
Overinflating a tire could cause
the tire to rupture and you or
others could be injured. Do not
exceed the maximum pressure
listed on the tire sidewall. See
Tire Sidewall Labeling 0332 and
Vehicle Load Limits 0200.
If the tire is overinflated by more
than 35 kPa (5 psi), the horn will
sound multiple times and the turn
signal lamp will continue to flash for
several seconds after filling stops.
To release and correct the pressure,
while the turn signal lamp is still
flashing, briefly press the center of the valve stem. When the
recommended pressure is reached,
the horn sounds once.
If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.
If the hazard warning flashers are
on, the tire fill alert visual feedback
will not work properly.
The TPMS will not activate the tire
fill alert properly under the following
conditions:
.
There is interference from an
external device or transmitter.
. The air pressure from the
inflation device is not sufficient
to inflate the tire.
. There is a malfunction in
the TPMS.
. There is a malfunction in the
horn or turn signal lamps.
. The identification code of the
TPMS sensor is not registered to
the system. .
The battery of the TPMS sensor
is low.
If the tire fill alert does not operate
due to TPMS interference, move the
vehicle about 1 m (3 ft) back or
forward and try again. If the tire fill
alert feature is not working, use a
tire pressure gauge.
TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
vehicle’s tires or replacing one or
more of the TPMS sensors. Also,
the TPMS sensor matching process
should be performed after replacing
a spare tire with a road tire
containing the TPMS sensor. The
malfunction light and the DIC
message should go off at the next
ignition cycle. The sensors are
matched to the tire/wheel positions,
using a TPMS relearn tool, in the
following order: driver side front tire,
passenger side front tire, passenger
side rear tire, and driver side rear.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
Vehicle Care 345
the tires have been rotated. See
Tire Pressure0337 and
Vehicle Load Limits 0200.
Reset the Tire Pressure Monitor
System. See Tire Pressure
Monitor Operation 0340.
Check that all wheel nuts are
properly tightened. See “Wheel
Nut Torque” underCapacities
and Specifications 0397, and
“Removing the Flat Tire and
Installing the Spare Tire” under
Tire Changing 0353.
{Warning
Rust or dirt on a wheel, or on the
parts to which it is fastened, can
make wheel nuts become loose
after time. The wheel could come
off and cause a crash. When
changing a wheel, remove any
rust or dirt from places where the
wheel attaches to the vehicle. In
an emergency, a cloth or a paper
(Continued)
Warning (Continued)
towel can be used; however, use
a scraper or wire brush later to
remove all rust or dirt.
Lightly coat the inner diameter of
the wheel hub opening with
wheel bearing grease after a
wheel change or tire rotation to
prevent corrosion or rust
buildup. Do not get grease on
the wheel mounting surface or
on the wheel nuts or bolts.
When It Is Time for New
Tires
Factors, such as maintenance,
temperatures, driving speeds,
vehicle loading, and road conditions
affect the wear rate of the tires.
Treadwear indicators are one way to
tell when it is time for new tires.
Treadwear indicators appear when
the tires have only 1.6 mm (1/16 in)
or less of tread remaining. Some
commercial truck tires may not have
treadwear indicators. See Tire
Inspection 0344 and
Tire Rotation 0344 for additional
information.
The rubber in tires ages over time.
This also applies to the spare tire,
if the vehicle has one, even if it is
never used. Multiple factors
including temperatures, loading
conditions, and inflation pressure
maintenance affect how fast aging

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
348 Vehicle Care
Different Size Tires and
Wheels
If wheels or tires are installed that
are a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be
affected.
{Warning
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This
increases the chance of a crash
and serious injury. Only use GM
specific wheel and tire systems(Continued)
Warning (Continued)
developed for the vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires 0346 and
Accessories and Modifications
0 285.
Uniform Tire Quality
Grading
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in
the United States. The grades
are molded on the sidewalls of
most passenger car tires. The
Uniform Tire Quality Grading
(UTQG) system does not apply
to deep tread, winter tires, compact spare tires, tires with
nominal rim diameters of
10 to 12 inches (25 to 30 cm),
or to some limited-production
tires.
While the tires available on
General Motors passenger cars
and light trucks may vary with
respect to these grades, they
must also conform to federal
safety requirements and
additional General Motors Tire
Performance Criteria (TPC)
standards.
Quality grades can be found
where applicable on the tire
sidewall between tread shoulder
and maximum section width. For
example:
Treadwear 200 Traction AA
Temperature A
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition To
These Grades.

Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13566622) - 2020 - CRC - 4/15/19
350 Vehicle Care
vehicle is significantly pulling to one
side or the other. Some slight pull to
the left or right, depending on the
crown of the road and/or other road
surface variations such as troughs
or ruts, is normal. If the vehicle is
vibrating when driving on a smooth
road, the tires and wheels may need
to be rebalanced. See your dealer
for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or
corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts, and
wheel nuts should be replaced.
If the wheel leaks air, replace it.
Some aluminum wheels can be
repaired. See your dealer if any of
these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset, and be
mounted the same way as the one it
replaces.Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.
{Warning
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.
Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or
odometer calibration, headlamp
aim, bumper height, vehicle
ground clearance, and tire or tire
chain clearance to the body and
chassis.
Used Replacement Wheels
{Warning
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.
Tire Chains
{Warning
If the vehicle has 265/65R18,
P265/65R18, P275/55R20,
or P285/45R22 size tires, do not
use tire chains. There is not
enough clearance. Tire chains
used on a vehicle without the
proper amount of clearance can
cause damage to the brakes,
suspension, or other vehicle
(Continued)