2020 CHEVROLET BLAZER warning light

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 241
may result in unpleasant engine and
transmission driving characteristics
and reduced fuel economy.
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
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
Control0194.
{Warning
Trailer sway can result in a crash
and in serious injury or death,
even if the vehicle is equipped
with TSC.
If the trailer begins to sway,
reduce vehicle speed by
gradually removing your foot from
the accelerator. Then pull over to
check the trailer and vehicle to
help correct possible causes,
including an improperly or
overloaded trailer, unrestrained
(Continued)
Warning (Continued)
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. SeeTowing
Equipment 0237 for trailer ratings
and hitch setup
recommendations.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are
designed with stiff sidewalls to help
prevent sway and to support heavy
loads. These features can make it
difficult to determine if the trailer tire
pressures are low only based on a
visual inspection.
Always check all trailer tire
pressures before each trip when the
tires are cool. Low trailer tire
pressure is a leading cause of trailer
tire blowouts.
Trailer tires deteriorate over time.
The trailer tire sidewall will show the
week and year the tire was

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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242 Driving and Operating
manufactured. Many trailer tire
manufacturers recommend
replacing tires more than six
years old.
Overloading is another leading
cause of trailer tire blowouts. Never
load your trailer with more weight
than the tires are designed to
support. The load rating is on the
trailer tire sidewall.
Always know the maximum speed
rating for the trailer tires before
driving. This may be significantly
lower than the vehicle tire speed
rating. The speed rating may be on
the trailer tire sidewall. If the speed
rating is not shown, the default
trailer tire speed rating is 105 km/h
(65 mph).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)0120.
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 070 and
Adding Equipment to the
Airbag-Equipped Vehicle 070.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 243
Vehicle Care
General Information
General Information . . . . . . . . . . 244
California Proposition65 Warning . . . . . . . . . . . . . . . . . 244
California Perchlorate Materials Requirements . . . . . 245
Accessories and Modifications . . . . . . . . . . . . . . . . 245
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 245
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 246
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 248
Engine Oil . . . . . . . . . . . . . . . . . . . . 253
Engine Oil Life System . . . . . . . 255
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 256
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 257
Engine Air Cleaner/Filter . . . . . . 257
Cooling System . . . . . . . . . . . . . . 259
Engine Overheating . . . . . . . . . . 264
Washer Fluid . . . . . . . . . . . . . . . . . 265
Brakes . . . . . . . . . . . . . . . . . . . . . . . 266
Brake Fluid . . . . . . . . . . . . . . . . . . . 267 Battery - North America . . . . . . 268
All-Wheel Drive . . . . . . . . . . . . . . . 269
Starter Switch Check . . . . . . . . . 269
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 269
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 269
Wiper Blade Replacement . . . . 270
Windshield Replacement . . . . . 271
Gas Strut(s) . . . . . . . . . . . . . . . . . . 271
Headlamp Aiming
Front Headlamp Aiming . . . . . . 273
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 273
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 273
LED Lighting . . . . . . . . . . . . . . . . . 273
Back-Up Lamps . . . . . . . . . . . . . . 273
Electrical System
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . . . 274
Electrical System Overload . . . 275
Fuses and Circuit Breakers . . . 275
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 276
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 279 Rear Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 282
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 284
All-Season Tires . . . . . . . . . . . . . . 285
Winter Tires . . . . . . . . . . . . . . . . . . 285
Summer Tires . . . . . . . . . . . . . . . . 286
Tire Sidewall Labeling . . . . . . . . 286
Tire Designations . . . . . . . . . . . . . 288
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 289
Tire Pressure . . . . . . . . . . . . . . . . . 291
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 293
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 293
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 294
Tire Inspection . . . . . . . . . . . . . . . . 298
Tire Rotation . . . . . . . . . . . . . . . . . 299
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 300
Buying New Tires . . . . . . . . . . . . . 301
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 302
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 302
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 304
Wheel Replacement . . . . . . . . . . 304

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266 Vehicle Care
Caution (Continued)
.Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
. Do not mix water with
ready-to-use washer fluid.
Water can cause the
solution to freeze and
damage the washer fluid
tank and other parts of the
washer system.
. When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
. Fill the washer fluid tank
only three-quarters full when
it is very cold. This allows
for fluid expansion if
freezing occurs, which could
damage the tank if it is
completely full.
Brakes
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or can
be heard all the time when the
vehicle is moving, except when
applying the brake pedal firmly.
{Warning
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
Caution
Continuing to drive with worn-out
brake pads could result in costly
brake repair. 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. See
Capacities and
Specifications 0352.
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

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Vehicle Care 267
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. SeeEngine
Compartment Overview 0248 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)
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 0122.
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 0339.
What to Add
Use only GM approved DOT 3
brake fluid from a clean, sealed
container. See Recommended
Fluids and Lubricants 0348.

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Vehicle Care 273
Headlamp Aiming
Front 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.
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.
Back-Up Lamps
To replace one of these bulbs:
1. Open the liftgate.

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Vehicle Care 295
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 pressure
shown on the Tire and Loading
Information label. SeeVehicle Load
Limits 0174.
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. Using the DIC, tire
pressure levels can be viewed. For
additional information and details
about the DIC operation and
displays see Driver Information
Center (DIC) (Base and Midlevel)
0 129 or
Driver Information Center (DIC)
(Uplevel) 0133.
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, attached to your vehicle,
shows the size of the original
equipment tires and the correct
inflation pressure for the tires when
they are cold. See
Vehicle Load
Limits 0174, for an example of the
Tire and Loading Information label
and its location. Also see Tire
Pressure 0291.
The TPMS can warn about a low
tire pressure condition but it does
not replace normal tire
maintenance. See Tire Inspection
0 298, Tire Rotation 0299 and
Tires 0284.
Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
(Continued)
Caution (Continued)
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.
Factory-installed Tire Inflator Kits
use a GM-approved liquid tire
sealant. Using non-approved tire
sealants could damage the TPMS
sensors. See Tire Sealant and
Compressor Kit 0307 for
information regarding the inflator kit
materials and instructions.
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

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296 Vehicle Care
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 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 0301.
. 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.
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.