
Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 265
If the CHANGE ENGINE OIL SOON message
comes back on when the vehicle is started,
the engine oil life system has not been
reset. Repeat the procedure.
Automatic Transmission Fluid
It is not necessary to check the transmission
fluid level. A transmission fluid leak is the
only reason for fluid loss. If a leak occurs,
take the vehicle to the dealer and have it
repaired as soon as possible.
Change the fluid at the intervals listed in
Maintenance Schedule0332, and be sure to
use the transmission fluid listed in
Recommended Fluids and Lubricants 0340.
Caution
Use of the incorrect automatic
transmission fluid may damage the
vehicle, and the damage may not be
covered by the vehicle warranty. Always
use the correct automatic transmission
fluid. See Recommended Fluids and
Lubricants 0340.
If you need to check the transmission fluid
level, take the vehicle to your dealer.
Engine Air Filter Life System
If equipped, this feature provides the engine
air filter’s remaining life and best timing for
a change. The timing to change an engine
air filter depends on driving and
environmental conditions.
When to Change the Engine Air Filter
When the Driver Information Center (DIC)
displays a message to replace the engine air
filter at the next oil change, follow this
timing.
When the DIC displays a message to replace
the engine air filter soon, replace the engine
air filter at the earliest convenience.
The system must be reset after the engine
air filter is changed.
If the DIC displays a message to check the
engine air filter system, see your dealer.
How to Reset the Engine Air Filter Life
System
To reset: 1. Place the vehicle in P (Park). 2. Display the Air Filter Life on the DIC. See
Driver Information Center (DIC) (Base and
Midlevel) 0107 or
Driver Information Center (DIC) (Uplevel)
0 110.
3. Press
Tto move to the Reset/Disable
display area. Select Reset then press the
thumbwheel.
4. Press the thumbwheel to confirm the reset.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the engine
compartment. See Engine Compartment
Overview 0257.
When to Inspect the Engine Air Cleaner/
Filter
If the vehicle is not equipped with the
engine air filter life system, see
Maintenance Schedule 0332 for intervals on
inspecting and replacing the engine air
cleaner/filter.
How to Inspect/Replace the Engine Air
Cleaner/Filter
Do not start the engine or have the engine
running with the engine air cleaner/filter
housing open. Before removing the engine

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)

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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:

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 275
Warning (Continued)
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 0254
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 not careful. See Jump
Starting - North America 0318 for tips on
working around a battery without
getting hurt.
Infrequent Usage: Remove the black,
negative (−) cable from the battery to keep
the battery from running down. Extended Storage: Remove the black,
negative (−) cable from the battery or use a
battery trickle charger.
All-Wheel Drive
Transfer Case
Under normal driving conditions, transfer
case fluid does not require maintenance
unless there is a fluid leak or unusual noise.
If required, have the transfer case serviced
by your dealer.
Automatic Transmission Shift Lock
Control Function Check
{Warning
When you are doing this inspection, the
vehicle could move suddenly. If the
vehicle moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room around the vehicle.
It should be parked on a level surface.
2. Apply the parking brake. Be ready to apply the regular brake immediately if
the vehicle begins to move. 3. With the engine off, turn the ignition on,
but do not start the engine. Without
applying the regular brake, try to move
the shift lever out of P (Park) with
normal effort. If the shift lever moves
out of P (Park), contact your dealer for
service.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check, the
vehicle could begin to move. You or
others could be injured and property
could be damaged. Make sure there is
room in front of the vehicle in case it
begins to roll. Be ready to apply the
regular brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the vehicle
facing downhill. Keeping your foot on the
regular brake, set the parking brake.
.To check the parking brake's holding
ability: With the engine running and the
transmission in N (Neutral), slowly remove

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282 Vehicle Care
FusesUsage
F2 Starter 1
F3 DC DC transformer 1
F4 –
F5 DC DC transformer 2
F6 –
F7 Front blower
F8 Starter 3
F9 –
F10 –
F11 –
F12 Front wiper
F13 Starter 2
F14 –
F15 Rear wiper
F16 –
F17 –
F18 –
F19 –
F20 –
F21 – Fuses
Usage
F22 Electronic brake control module
F23 Parking/Trailer lamps
F24 Right trailer stoplamp/ Turnlamp
F25 Steering column lock
F26 –
F27 Left trailer stoplamp/ Turnlamp
F28 –
F29 –
F30 Washer pump F31 Spare/Right low-beam headlamp
F32 Left low-beam headlamp
F33 High-beam headlamp shutter/ Fog lamps
F34 Horn F35 –
F36 Right low-beam/Left high-beam headlamp Fuses
Usage
F37 Spare/Right high-beam headlamp
F38 Automatic headlamp leveling motor
F39 Transmission control module
F40 Left rear bus electrical center/DC DC ignition
F41 Instrument cluster
F42 Heating, ventilation, and air conditioning/
Central gateway
module run/crank
F43 Reflective light alert display
F44 Electronic brake control module/Electric brake
booster/Run/crank
F45 –
F46 –
F47 –
F48 –
F49 Interior rearview mirror

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 283
FusesUsage
F50 Fuel system control module/Fuel tank zone
module run/crank
F51 Heated steering wheel
F52 Air conditioning clutch
F53 Coolant pump
F54 –
F55 –
F56 –
F57 Engine control module/ Ignition
F58 Transmission control module/Ignition
F59 Engine control module battery
F60 –
F61 O2 sensor 1/ Aeroshutter/Mass air
flow sensor
F62 Engine control module–odd
F63 O2 sensor 2 Fuses
Usage
F64 Engine control module–even
F65 Engine control module powertrain 1
F66 Engine control module powertrain 2
F67 Engine control module powertrain 3
F68 –
F69 –
F70 –
F71 –
F72 –
F73 –
F74 –
F75 –
F76 –
F77 – Relays
Usage
K1 Starter 1
K2 Run/Crank
K3 Starter 3
K4 –
K5 –
K6 –
K7 Engine control module
K8 Air conditioning
K9 –
K10 Starter 2

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284 Vehicle Care
Instrument Panel Fuse Block
The instrument panel fuse block is inside the
center console on the passenger side of the
vehicle.
Remove the fuse access door by inserting a
coin or tool into the slot of the access door.
To remove a fuse, use the fuse puller
located in the Engine Compartment Fuse
block.
The vehicle may not be equipped with all of
the fuses, relays, and features shown.Fuses Usage
F1 Body control module 6 Fuses Usage
F2 Diagnostic link/Central gateway module
F3 Electric steering column lock
F4 –
F5 –
F6 Heating, ventilation, and air conditioning
F7 Body control module 3
F8 –
F9 Right front heated seat
F10 Airbag/Seatbelt F11 –
F12 Amplifier/Noise control module
F13 Body control module 7
F14 Left front heated seat F15 –
F16 Sunroof F17 –
F18 Instrument cluster