2020 CHEVROLET BLAZER check engine light

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
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-
13557845) - 2020 - CRC - 3/24/20
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-
13557845) - 2020 - CRC - 3/24/20
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-
13557845) - 2020 - CRC - 3/24/20
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-
13557845) - 2020 - CRC - 3/24/20
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.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13557845) - 2020 - CRC - 3/24/20
322 Vehicle Care
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 0184.
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.