warning CHEVROLET BLAZER 2021 Owner's Manual

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
262 Vehicle Care
11. Remote Negative (-) Battery Terminal.SeeJump Starting - North America 0318.
Engine Oil
To ensure proper engine performance and
long life, careful attention must be paid to
engine oil. Following these simple, but
important steps will help protect your
investment:
.Use engine oil approved to the proper
specification and of the proper viscosity
grade. See “Selecting the Right Engine
Oil” in this section.
.Check the engine oil level regularly and
maintain the proper oil level. See
“Checking Engine Oil” and“When to Add
Engine Oil” in this section.
.Change the engine oil at the appropriate
time. SeeEngine Oil Life System 0264.
.Always dispose of engine oil properly. See
“What to Do with Used Oil” in this
section.
Checking Engine Oil
Check the engine oil level regularly, every
650 km (400 mi), especially prior to a long
trip. The engine oil dipstick handle is a loop.
See Engine Compartment Overview 0257 for
the location.
{Warning
The engine oil dipstick handle may be
hot; it could burn you. Use a towel or
glove to touch the dipstick handle.
If a low oil Driver Information Center (DIC)
message displays, check the oil level.
Follow these guidelines:
.To get an accurate reading, park the
vehicle on level ground. Check the engine
oil level after the engine has been off for
at least two hours. Checking the engine
oil level on steep grades or too soon after
engine shutoff can result in incorrect
readings. Accuracy improves when
checking a cold engine prior to starting.
Remove the dipstick and check the level.
.If unable to wait two hours, the engine
must be off for at least 15 minutes if the
engine is warm, or at least 30 minutes if
the engine is not warm. Pull out the
dipstick, wipe it with a clean paper towel
or cloth, then push it back in all the way.
Remove it again, keeping the tip down,
and check the level.
When to Add Engine Oil
2.0L L4 Engine
2.5L L4 Engine
3.6L V6 Engine
If the oil is below the cross-hatched area at
the tip of the dipstick and the engine has
been off for at least 15 minutes, add 1 L (1
qt) of the recommended oil and then

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
264 Vehicle Care
What to Do with Used Oil
Used engine oil contains certain elements
that can be unhealthy for your skin and
could even cause cancer. Do not let used oil
stay on your skin for very long. Clean your
skin and nails with soap and water, or a
good hand cleaner. Wash or properly
dispose of clothing or rags containing used
engine oil. See the manufacturer's warnings
about the use and disposal of oil products.
Used oil can be a threat to the environment.
If you change your own oil, be sure to drain
all the oil from the filter before disposal.
Never dispose of oil by putting it in the
trash or pouring it on the ground, into
sewers, or into streams or bodies of water.
Recycle it by taking it to a place that
collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that
indicates when to change the engine oil and
filter. This is based on a combination of
factors which include engine revolutions,
engine temperature, and miles driven. Based
on driving conditions, the mileage at which
an oil change is indicated can varyconsiderably. For the oil life system to work
properly, the system must be reset every
time the oil is changed.
When the system has calculated that oil life
has been diminished, it indicates that an oil
change is necessary. A CHANGE ENGINE OIL
SOON message comes on. Change the oil as
soon as possible within the next 1 000 km
(600 mi). It is possible that, if driving under
the best conditions, the oil life system
might indicate that an oil change is not
necessary for up to a year. The engine oil
and filter must be changed at least once a
year and, at this time, the system must be
reset. Your dealer has trained service people
who will perform this work and reset the
system. It is also important to check the oil
regularly over the course of an oil drain
interval and keep it at the proper level.
If the system is ever reset accidentally, the
oil must be changed at 5 000 km (3,000 mi)
since the last oil change. Remember to reset
the oil life system whenever the oil is
changed.
How to Reset the Engine Oil Life System
Reset the system whenever the engine oil is
changed so that the system can calculate
the next engine oil change. To reset the
system:
1. Display the REMAINING OIL LIFE on the DIC. See Driver Information Center (DIC)
(Base and Midlevel) 0107 or
Driver Information Center (DIC) (Uplevel)
0 110.
2. Press and hold the thumbwheel on the DIC while the Oil Life display is active.
3. Confirm yes, and the oil life will change to 100%.
The oil life system can also be reset as
follows: 1. Place the ignition in Service Mode. See Ignition Positions 0200.
2. Display REMAINING OIL LIFE on the DIC menu. See Driver Information Center
(DIC) (Base and Midlevel) 0107 or
Driver Information Center (DIC) (Uplevel)
0 110.
3. Fully press and release the accelerator pedal three times within five seconds.
4. If the display changes to 100%, the system is reset.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
266 Vehicle Care
air cleaner/filter, make sure that the engine
air cleaner/filter housing and nearby
components are free of dirt and debris. Do
not clean the engine air cleaner/filter or
components with water or compressed air.
To inspect or replace the air cleaner/filter:
2.0L L4 Engine
1. Remove the five screws on top of the engine air cleaner/filter cover.
2. Lift and remove the engine air cleaner/ filter cover.
3. Pull out the air cleaner/filter.
{Warning
If part replacement is necessary, the part
must be replaced with one of the same
part number or with an equivalent part.
Use of a replacement part without the
same fit, form, and function may result
in personal injury or damage to the
vehicle.
4. Inspect or replace the engine air cleaner/ filter.
5. Reverse Steps 1–3 to reinstall the engine air cleaner/filter cover.
6. If equipped, reset the engine air filter life system after replacing the engine air
filter. See Engine Air Filter Life System
0 265.
2.5L L4 Engine
1. Remove the five screws on top of the engine air cleaner/filter cover.
2. Lift and remove the engine air cleaner/ filter cover.
3. Pull out the air cleaner/filter.
4. Inspect or replace the engine air cleaner/ filter.
5. Reverse Steps 1–3 to reinstall the engine air cleaner/filter cover.
6. If equipped, reset the engine air filter life system after replacing the engine air
filter. See Engine Air Filter Life System
0 265.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 267
3.6L V6 Engine
1. Remove the five screws on top of the engine air cleaner/filter cover.
2. Lift and remove the engine air cleaner/ filter cover.
3. Pull out the air cleaner/filter.
4. Inspect or replace the engine air cleaner/ filter.
5. Reverse Steps 1–3 to reinstall the engine air cleaner/filter cover.
6. If equipped, reset the engine air filter life system after replacing the engine air
filter. See Engine Air Filter Life System
0 265.
{Warning
Operating the engine with the air
cleaner/filter off can cause you or others
to be burned. Use caution when working
on the engine. Do not start the engine or
drive the vehicle with the air cleaner/
filter off, as flames may be present if the
engine backfires.
Caution
If the air cleaner/filter is off, dirt can
easily get into the engine, which could
damage it. Always have the air cleaner/
filter in place when driving.
Cooling System
The cooling system allows the engine to
maintain the correct working temperature.
2.0L L4 Engine
1. Engine Cooling Fan (Out of View)
2. Engine Coolant Surge Tank and
Pressure Cap

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
268 Vehicle Care
2.5L L4 Engine
1. Engine Cooling Fan (Out of View)
2. Engine Coolant Surge Tank andPressure Cap
3.6L V6 Engine
1. Engine Cooling Fan (Out of View)
2. Engine Coolant Surge Tank andPressure Cap
{Warning
An underhood electric fan can start up
even when the engine is not running and
can cause injury. Keep hands, clothing,
and tools away from any underhood
electric fan.
{Warning
Do not touch heater or radiator hoses,
or other engine parts. They can be very
hot and can burn you. Do not run the
engine if there is a leak; all coolant could
leak out. That could cause an engine fire
and can burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the vehicle is filled
with DEX-COOL engine coolant. This coolant
needs to be checked and replaced at
appropriate intervals. See Maintenance
Schedule 0332.
The following explains the cooling system
and how to check and add coolant when it
is low. If there is a problem with engine
overheating, see Engine Overheating 0271.
What to Use
{Warning
Do not touch heater or radiator hoses,
or other engine parts. They can be very
hot and can burn you. Do not run the
(Continued)

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Vehicle Care 269
Warning (Continued)
engine if there is a leak; all coolant could
leak out. That could cause an engine fire
and can burn you. Fix any leak before
driving the vehicle.
Use a 50/50 mixture of clean, drinkable
water and DEX-COOL coolant. This mixture:
.Gives freezing protection down to −37 °C
(−34 °F), outside temperature.
.Gives boiling protection up to 129 °C
(265 °F), engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
Caution
Do not use anything other than a mix of
DEX-COOL coolant that meets GM
Standard GMW3420 and clean, drinkable
water. Anything else can cause damage
to the engine cooling system and the
vehicle, which would not be covered by
the vehicle warranty. Never dispose of engine coolant by putting
it in the trash, or by pouring it on the
ground or into sewers, streams, or bodies of
water. Have the coolant changed by an
authorized service center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface when
checking the coolant level.
Check to see if coolant is visible in the
coolant surge tank. If the coolant inside the
coolant surge tank is boiling, do not do
anything else until it cools down. See
Engine
Overheating 0271. The coolant surge tank is in the engine
compartment on the driver side of the
vehicle. See
Engine Compartment Overview
0 257.
How to Add Coolant to the Coolant
Surge Tank
{Warning
Spilling coolant on hot engine parts can
burn you. Coolant contains ethylene
glycol and it will burn if the engine parts
are hot enough.
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
270 Vehicle Care
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain water or
the wrong mixture, the engine could get
too hot but there would not be an
overheat warning. The engine could catch
fire and you or others could be burned.
Caution
Failure to follow the specific coolant fill
procedure could cause the engine to
overheat and could cause system
damage. If coolant is not visible in the
surge tank, contact your dealer.
If no problem is found, check to see if
coolant is visible in the coolant surge tank.
If coolant is visible but the coolant level is
not at or above the indicated mark, add a
50/50 mixture of clean, drinkable water and
DEX-COOL coolant. Be sure the cooling
system, including the coolant surge tank
pressure cap, is cool before you do it.
2.5L L4 and 3.6L V6 Engines
1. Remove the coolant surge tank pressure cap when the cooling system, including
the coolant surge tank pressure cap and
upper radiator hose, is no longer hot.
Turn the pressure cap slowly
counterclockwise about one-quarter of a
turn. If you hear a hiss, wait for that to
stop. This will allow any pressure still
left to be vented out the discharge hose.
2. Keep turning the pressure cap slowly and remove it.
3. Fill the coolant surge tank with theproper mixture to the indicated
level mark.
4. With the coolant surge tank pressure cap off, start the engine and let it run until
you can feel the upper radiator hose
getting hot. Watch out for the engine
cooling fan.
By this time, the coolant level inside the
coolant surge tank may be lower. If the
level is lower, add more of the proper
mixture to the coolant surge tank until
the level reaches the indicated
level mark.
5. Replace the pressure cap tightly.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 271
6. Verify coolant level after the engine isshut off and the coolant is cold.
If necessary, repeat coolant fill procedure
Steps 1–6.
If the coolant still is not at the proper
level when the system cools down again,
see your dealer.
Caution
If the pressure cap is not tightly installed,
coolant loss and engine damage may
occur. Be sure the cap is properly and
tightly secured.
2.0L L4 Engine Only - Automatic Coolant
Service Fill Instructions
If equipped, this feature assists in filling and
removing air from the cooling system after
service of components or when coolant is
added after being too low.
To activate the fill and air removal process:
1. With a cold system, add coolant to the indicated mark on the surge tank.
2. Replace the cap on the surge tank.
3. Connect the vehicle to a battery charger.
4. Turn the ignition to Service Mode. See Ignition Positions 0200. 5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the accelerator
and the brake for two seconds, then
release.
At the end of the cycle, check the coolant
level in the surge tank and add coolant if it
is low. Turn off the vehicle, allow the
Electronic Control Module (ECM) to go to
sleep, about two minutes, and repeat
Steps 4–7.
Listen for pump activation and movement of
the control valves while watching the level
of the coolant in the surge tank. If the tank
empties, turn the ignition off, carefully
remove the surge tank cap, refill to the
indicated mark, and repeat Steps 4–7. The
fill and air removal process will run for
approximately 10 minutes.
Engine Overheating
The vehicle has several indicators to warn of
the engine overheating.
There is an engine coolant temperature
gauge on the instrument cluster. See Engine
Coolant Temperature Gauge 096. The
vehicle may also display a message on the
Driver Information Center (DIC). If the decision is made not to lift the hood
when this warning appears, get service help
right away. See
Roadside Assistance Program
0 352.
If the decision is made to lift the hood,
make sure the vehicle is parked on a level
surface. Then check to see if the engine
cooling fan is running. If the engine is
overheating, the fan should be running. If it
is not, do not continue to run the engine.
Have the vehicle serviced.
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.
If Steam Is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high (Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
272 Vehicle Care
Warning (Continued)
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If No Steam Is Coming from the Engine
Compartment
If an engine overheat warning is displayed
but no steam can be seen or heard, the
problem may not be too serious. Sometimes
the engine can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
If the overheat warning is displayed with no
sign of steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest fan
speed. Open the windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or N (Neutral), and
let the engine idle. If the engine coolant temperature gauge is
no longer in the overheated area, the
vehicle can be driven. Continue to drive the
vehicle slowly for about 10 minutes. Keep a
safe distance from the vehicle in front. If the
warning does not come back on, continue to
drive normally and have the cooling system
checked for proper fill and function.
If the warning continues, pull over, stop, and
park the vehicle right away.
If there is no sign of steam, idle the engine
for three minutes while parked. If the
warning is still displayed, turn off the
engine until it cools down.
Washer Fluid
What to Use
When windshield washer fluid is needed, be
sure to read the manufacturer's instructions
before use. If operating the vehicle in an
area where the temperature may fall below
freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
Open the cap with the washer symbol on it.
Add washer fluid until the tank is full. See
Engine Compartment Overview
0257 for
reservoir location.
Caution
.Do not use washer fluid that contains
any type of water repellent coating.
This can cause the wiper blades to
chatter or skip.
.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.
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 273
Caution (Continued)
.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 linings have built-in wear
indicators that make a high-pitched warning
sound when the brake linings are worn and
new linings 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
linings could result in costly brake
repairs.
Some driving conditions or climates can
cause a brake squeal when the brakes are
first applied, clearing up following several
applications. 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 linings for wear
and evenly tighten wheel nuts in the proper
sequence to torque specifications. See
Capacities and Specifications 0345.
Brake pads should be replaced as complete
axle 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 can
change in many ways if the wrong 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 0257 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: