warning light CHEVROLET BLAZER 2021 Workshop Manual

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
278 Vehicle Care
Liftgate
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.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 297
When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as
intended. TPMS malfunctions may occur for
a variety of reasons, including the
installation of replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on
your vehicle to ensure that the replacement
or alternate tires and wheels allow the
TPMS to continue to function properly.
SeeTire Pressure Monitor Operation 0297.
See Radio Frequency Statement 0357.
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
pressure shown on the Tire and Loading
Information label. See Vehicle Load Limits
0 197.
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)
0 107 or
Driver Information Center (DIC) (Uplevel)
0 110. 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 0197, for
an example of the Tire and Loading
Information label and its location. Also see
Tire Pressure 0294.
The TPMS can warn about a low tire
pressure condition but it does not replace
normal tire maintenance. See Tire Inspection
0 300, Tire Rotation 0300 and
Tires 0287.
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
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Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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298 Vehicle Care
Caution (Continued)
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 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 0302.
.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.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 299
{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 Labeling0289 and
Vehicle Load Limits 0197.
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.
The TPMS sensor matching process should
also 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 tire. See your
dealer for service or to purchase a relearn
tool. A TPMS relearn tool can also be
purchased. See Tire Pressure Monitor Sensor
Activation Tool at
www.gmtoolsandequipment.com or call
1-800-GM TOOLS (1-800-468-6657).
There are two minutes to match the first
tire/wheel position, and five minutes overall
to match all four tire/wheel positions. If it
takes longer, the matching process stops
and must be restarted.
The TPMS sensor matching process is:
1. Set the parking brake.
2. Place the vehicle in Service Mode. See Ignition Positions 0200.
3. Make sure the Tire Pressure info page option is turned on. The info pages on
the DIC can be turned on and off
through the Options menu. See Driver
Information Center (DIC) (Base and
Midlevel) 0107 or
Driver Information Center (DIC) (Uplevel)
0 110.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Vehicle Care 301
Use this rotation pattern when rotating
the tires.
Do not include the compact spare tire
in the tire rotation.
Adjust the front and rear tires to the
recommended inflation pressure on the
Tire and Loading Information label after
the tires have been rotated. SeeTire
Pressure 0294 and
Vehicle Load Limits 0197.
Reset the Tire Pressure Monitor System.
See Tire Pressure Monitor Operation
0 297. Check that all wheel nuts are properly
tightened. See
“Wheel Nut Torque”
under Capacities and Specifications
0 345, and “Removing the Flat Tire and
Installing the Spare Tire” underTire
Changing 0313.
{Warning
Rust or dirt on a wheel, or on the
parts to which it is fastened, can
cause wheel nuts to become loose
over 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 paper 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.
{Warning
Do not apply grease to the wheel
mounting surface, wheel conical
seats, or the wheel nuts or bolts.
Grease applied to these areas could
cause a wheel to become loose or
come off, resulting in a crash.
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

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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302 Vehicle Care
1.6 mm (1/16 in) or less of tread remaining.
SeeTire Inspection 0300 and
Tire Rotation 0300 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 takes place. GM recommends
that tires, including the spare if equipped,
be replaced after six years, regardless of
tread wear. To identify the age of a tire, use
the tire manufacture date, which is the last
four digits of the DOT Tire Identification
Number (TIN) molded into one side of the
tire sidewall. The last four digits of the TIN
indicate the tire manufactured date. The
first two digits represent the week and the
last two digits, the year. For example, the
third week of the year 2020 would have a
4-digit DOT date of 0320. Week 01 is the
first full week (Sunday through Saturday) of
each year.
Vehicle Storage
Tires age when stored normally mounted on
a parked vehicle. Park a vehicle that will be
stored for at least a month in a cool, dry,
clean area away from direct sunlight to slow aging. This area should be free of grease,
gasoline, or other substances that can
deteriorate rubber.
Parking for an extended period can cause
flat spots on the tires that may result in
vibrations while driving. When storing a
vehicle for at least a month, remove the
tires or raise the vehicle to reduce the
weight from the tires.
Buying New Tires
GM has developed and matched specific
tires for the vehicle. The original
equipment tires installed were designed
to meet General Motors Tire
Performance Criteria Specification (TPC
Spec) system rating. When replacement
tires are needed, GM strongly
recommends buying tires with the same
TPC Spec rating.
GM's exclusive TPC Spec system
considers over a dozen critical
specifications that impact the overall
performance of the vehicle, including
brake system performance, ride and
handling, traction control, and tire
pressure monitoring performance. GM's
TPC Spec number is molded onto the
tire's sidewall near the tire size. If the
tires have an all-season tread design,
the TPC Spec number will be followed
by MS for mud and snow. See
Tire
Sidewall Labeling 0289 for additional
information.
GM recommends replacing worn tires in
complete sets of four. Uniform tread
depth on all tires will help to maintain
the performance of the vehicle. Braking
and handling performance may be
adversely affected if all the tires are not
replaced at the same time. If proper
rotation and maintenance have been
done, all four tires should wear out at
about the same time. However, if it is
necessary to replace only one axle set
of worn tires, place the new tires on
the rear axle. See Tire Rotation0300.
{Warning
Tires could explode during improper
service. Attempting to mount or
dismount a tire could cause injury or
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Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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304 Vehicle Care
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.
Treadwear
The treadwear grade is a comparative
rating based on the wear rate of the
tire when tested under controlledconditions on a specified government
test course. For example, a tire graded
150 would wear one and one-half (1½)
times as well on the government course
as a tire graded 100. The relative
performance of tires depends upon the
actual conditions of their use, however,
and may depart significantly from the
norm due to variations in driving habits,
service practices and differences in road
characteristics and climate.
Traction
The traction grades, from highest to
lowest, are AA, A, B, and C. Those
grades represent the tire's ability to
stop on wet pavement as measured
under controlled conditions on specified
government test surfaces of asphalt and
concrete. A tire marked C may have
poor traction performance. Warning:
The traction grade assigned to this tire
is based on straight-ahead braking
traction tests, and does not include
acceleration, cornering, hydroplaning,
or peak traction characteristics.
Temperature
The temperature grades are A (the
highest), B, and C, representing the
tire's resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled conditions
on a specified indoor laboratory test
wheel. Sustained high temperature can
cause the material of the tire to
degenerate and reduce tire life, and
excessive temperature can lead to
sudden tire failure. The grade C
corresponds to a level of performance
which all passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B and A
represent higher levels of performance
on the laboratory test wheel than the
minimum required by law. Warning:
The temperature grade for this tire is
established for a tire that is properly
inflated and not overloaded. Excessive
speed, underinflation, or excessive
loading, either separately or in
combination, can cause heat buildup
and possible tire failure.

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Vehicle Care 305
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider an
alignment check if there is unusual tire wear
or the 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 235/55R20 or 265/45R21
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 parts.
The area damaged by the tire chains
could cause loss of control and a crash.
Use another type of traction device only
if its manufacturer recommends it for the
vehicle's tire size combination and road
conditions. Follow that manufacturer's
instructions. To avoid vehicle damage,
drive slow and readjust or remove the
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 319
1. Discharged Battery Positive (+)Terminal
2. Discharged Battery Remote Negative (–) Terminal
3. Good Battery Negative (–) Terminal
4. Good Battery Positive (+) Terminal
The jump start positive (+) terminal (1) and
the negative remote negative terminal (2)
for the discharged battery are on the driver
side of the vehicle.
The jump start positive (+) terminal (4) and
negative (-) terminal (3) are on the battery
of the vehicle providing the jump start.
1. Check the other vehicle. It must have a 12-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. Position the two vehicles so that they are not touching.
3. Set the parking brake firmly and put the shift lever in P (Park) with an automatic
transmission, or Neutral with a manual
transmission. See Shifting Into Park
0 205.
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. Turn off all lights and accessories in both vehicles, except
the hazard warning flashers if needed.
{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.
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.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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368 Index
IndexA
Accessories and Modifications . . . . . . . . . . . 254
Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . 205
Active Fuel Management . . . . . . . . . . . . . . . . 206
Adaptive Cruise Control . . . . . . . . . . . . . . . . . . . 217
Add-On Electrical Equipment . . . . . . . . . . . . . 252
Additional InformationOnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
Additional Maintenance and Care . . . . . . . . 337
Adjustments Lumbar, Front Seats . . . . . . . . . . . . . . . . . . . . 36
Agreements Trademarks and License . . . . . . . . . . . . . . . . 173
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . 265
Air Conditioning . . . . . . . . . . . . . . . . . . . . . . . . . .182
Air Filter
Life System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Air Filter, Passenger Compartment . . . . . . . 186
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
How Does an Airbag Restrain? . . . . . . . . . . 54
Passenger Sensing System . . . . . . . . . . . . . . 55
What Makes an Airbag Inflate? . . . . . . . . . 54
What Will You See after an AirbagInflates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
When Should an Airbag Inflate? . . . . . . . . 53
Where Are the Airbags? . . . . . . . . . . . . . . . . 52 Airbags
Adding Equipment to the Vehicle . . . . . . . 59
Passenger Status Indicator . . . . . . . . . . . . . . 99
Readiness Light . . . . . . . . . . . . . . . . . . . . . . . . . 98
Servicing Airbag-Equipped Vehicles . . . . . . 58
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Alarm
Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . 23
Alert Lane Change . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Side Blind Zone (SBZA) . . . . . . . . . . . . . . . . . 236
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 288
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 210, 275
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . .134
Antenna Multi-band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Antilock Brake System (ABS) . . . . . . . . . . . . . 210 Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . 102
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
Apple CarPlay and Android Auto . . . . . . . . . 163
Armrest Storage . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Assistance Program, Roadside . . . . . . . . . . . . 352
Assistance Systems for Driving . . . . . . . . . . 230
Assistance Systems for Parking and Backing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227