check engine CHEVROLET BLAZER 2020 User Guide

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13557845) - 2020 - CRC - 3/24/20
Driving and Operating 171
{Warning
Wet brakes can cause crashes.
They might not work as well in a
quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under the vehicle's
tires so they actually ride on the
water. This can happen if the road iswet enough and you are going fast
enough. When the vehicle is
hydroplaning, it has little or no
contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.
Allow extra following distance.
. Pass with caution.
. Keep windshield wiping
equipment in good shape.
. Keep the windshield washer fluid
reservoir filled.
. Have good tires with proper
tread depth. See Tires0284.
. Turn off cruise control.
. Activate All-Wheel Drive (AWD)
mode. See Driver Mode Control
0 196.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips include:
.
Keep the vehicle serviced and in
good shape.
. Check all fluid levels and brakes,
tires, cooling system, and
transmission.
. Shift to a lower gear when going
down steep or long hills.
{Warning
Using the brakes to slow the
vehicle on a long downhill slope
can cause brake overheating, can
reduce brake performance, and
could result in a loss of braking.
Shift the transmission to a lower
gear to let the engine assist the
brakes on a steep downhill slope.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13557845) - 2020 - CRC - 3/24/20
Driving and Operating 183
2. Check the heater cord fordamage. If it is damaged, do
not use it. See your dealer for
a replacement. Inspect the
cord for damage yearly.
3. Plug the heater cord into the connector in the front bumper.
4. Plug the cord into a grounded 110-volt AC outlet that is
protected by a ground fault
detection function.
{Warning
Improper use of the heater cord
or an extension cord can damage
the cord and may result in
overheating and fire.
. Plug the cord into a
three-prong electrical utility
receptacle that is protected
by a ground fault detection
function. An ungrounded
outlet could cause an
electric shock.
. Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension
cord in good operating
condition, or using a
damaged heater or
extension cord, could make
(Continued)
Warning (Continued)
it overheat and cause a fire,
property damage, electric
shock, and injury.
. Do not operate the vehicle
with the heater cord
permanently attached to the
vehicle. Possible heater
cord and thermostat
damage could occur.
. While in use, do not let the
heater cord touch vehicle
parts or sharp edges.
. Before starting the vehicle,
unplug the cord. Keep the
cord away from any moving
parts.
5. Before starting the engine, be sure to unplug and store the
cord as it was before to keep it
away from moving engine
parts. If you do not, it could be
damaged.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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192 Driving and Operating
may be heard while this test is going
on, and the brake pedal may move
slightly. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
0 123.
ABS does not change the time
needed to get a foot on the brake
pedal and does not always
decrease stopping distance. If you
get too close to the vehicle ahead,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room ahead to stop,
even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly.
Hearing or feeling ABS operate is
normal.
Braking in Emergencies
ABS allows steering and braking at
the same time. In many
emergencies, steering can help
even more than braking.
Electric Parking Brake
The vehicle has an Electric Parking
Brake (EPB). The EPB can always
be activated, even if the ignition is off. To prevent draining the battery,
avoid repeated cycles of the EPB
system when the engine is not
running.
The system has a
Y, PARK, orf
Electric Parking Brake light, and
some vehicles may have a
8
Service Parking Brake light. See
Electric Parking Brake Light
0123
and
Service Electric Parking Brake Light
0 123.
Before leaving the vehicle, check for
the Electric Parking Brake light to
ensure that the EPB is applied.
EPB Apply
To apply the EPB: 1. Be sure the vehicle is at a complete stop.
2. Press the EPB switch momentarily.
The Electric Parking Brake light will
flash and then stay on once the
EPB is fully applied. If the light
flashes continuously, then the EPB
is only partially applied, the vehicle
is in Service Mode, or there is a

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13557845) - 2020 - CRC - 3/24/20
Driving and Operating 195
braking pressure to any one of the
vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
TCS or StabiliTrak/ESC begins to
limit wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow. TCS and
StabiliTrak/ESC will automatically
turn on when cruise control is set.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
SeeIf the Vehicle Is Stuck 0173
and “Turning the Systems Off and
On” later in this section.
The indicator light for both systems
is in the instrument cluster. This
light will:
.
Flash when TCS is limiting
wheel spin
. Flash when StabiliTrak/ESC is
activated
. Turn on and stay on when either
system is not working
If either system fails to turn on or to
activate, a message may display in
the Driver Information Center (DIC),
and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.
If
dcomes on and stays on:
1. Stop the vehicle. 2. Turn the engine off and wait
15 seconds.
3. Start the engine.
4. Drive the vehicle.
If
dcomes on and stays on, the
vehicle may need more time to
diagnose the problem. If the
condition persists, see your dealer.
Turning the Systems Off
and On

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 231
Warning (Continued)
.Fully open the air outlets on
or under the instrument
panel.
. Adjust the climate control
system to a setting that
brings in only outside air.
See “Climate Control
Systems” in the Index.
For more information about
carbon monoxide, see Engine
Exhaust 0186.
Towing a trailer requires experience.
The combination of the vehicle and
trailer is longer and not as
responsive as the vehicle itself. Get
used to the handling and braking of
the combination by driving on a
level road surface before driving on
public roads.
The trailer structure, the tires, and
the brakes must all be rated to carry
the intended cargo. Inadequate
trailer equipment can cause the
combination to operate in an
unexpected or unsafe manner. Before driving, inspect all trailer
hitch parts and attachments, safety
chains, electrical connectors, lamps,
tires, and mirrors. See
Towing
Equipment 0237. If the trailer has
electric brakes, start the
combination moving and then
manually apply the trailer brake
controller to check that the trailer
brakes work.
During the trip, occasionally check
that the cargo and trailer are secure
and that the lamps and any trailer
brakes are working.
Towing with a Stability Control
System
When towing, the stability control
system might be heard. The system
reacts to vehicle movement caused
by the trailer, which mainly occurs
during cornering. This is normal
when towing heavier trailers.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving without a trailer. This can
help to avoid heavy braking and
sudden turns.
Passing
More passing distance is needed
when towing a trailer. The
combination of the vehicle and
trailer will not accelerate as quickly
and is much longer than the vehicle
alone. It is necessary to go much
farther beyond the passed vehicle
before returning to the lane. Pass
on level roadways. Avoid passing
on hills if possible.
Backing Up
Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move that hand to
the left. To move the trailer to the
right, move that hand to the right.
Always back up slowly and,
if possible, have someone
guide you.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 233
4. Reapply the brake pedal. Thenapply the parking brake and
shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
. Shift into a gear.
. Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when used to tow trailers. See
theMaintenance Schedule 0339.
It is especially important to check
the engine oil, axle lubricant, belts,
cooling system, and brake system
before and during each trip. Check periodically that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See
Engine Overheating
0 264.
Trailer Towing
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer
for important information about
towing a trailer with the vehicle.
Trailer Weight
{Warning
Never exceed the towing capacity
for your vehicle.
Safe trailering requires monitoring
the weight, speed, altitude, road
grades, outside temperature,
dimensions of the front of the trailer,
and how frequently the vehicle is
used to tow a trailer.
Trailer Weight Ratings
When towing a trailer, the combined
weight of the vehicle, vehicle
contents, trailer, and trailer contents
must be below all of the maximum
weight ratings for the vehicle,
including:
. GCWR: Gross Combined Weight
Rating
. GVWR: Gross Vehicle Weight
Rating

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

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 253
1.Engine Air Cleaner/Filter 0257.
2. Engine Oil Fill Cap. See Engine Oil 0253.
3. Engine Oil Dipstick. See Engine Oil 0253.
4. Engine Cooling Fan (Out of View). See Cooling System
0 259.
5. Brake Fluid Reservoir. See Brake Fluid 0267.
6. Battery - North America 0268.
7. Engine Coolant Surge Tank and Pressure Cap. See
Cooling System 0259.
8. Positive (+) Battery Terminal. See Jump Starting - North
America 0321.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 265.
10. Engine Compartment Fuse
Block 0276.
11. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0321.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. See Engine Oil
Life System 0255.
. 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
0
248 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.