2021 CHEVROLET BLAZER check engine

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Instruments and Controls 101
If the light continues to flash, find a safe
place to park. Turn the vehicle off and wait
at least 10 seconds before restarting the
engine. If the light is still flashing, follow
the previous guidelines and see your dealer
for service as soon as possible.
If the light is on steady :A malfunction has
been detected. Diagnosis and service may be
required.
Check the following:
.If fuel has been added to the vehicle
using the capless fuel funnel adapter,
make sure that it has been removed. See
“Filling the Tank with a Portable Gas Can”
under Filling the Tank 0240. The
diagnostic system can detect if the
adapter has been left installed in the
vehicle, allowing fuel to evaporate into
the atmosphere. A few driving trips with
the adapter removed may turn off the
light.
.Poor fuel quality can cause inefficient
engine operation and poor driveability,
which may go away once the engine is
warmed up. If this occurs, change the fuel
brand. It may require at least one full
tank of the proper fuel to turn the light
off. See Recommended Fuel 0239.
If the light remains on, see your dealer.
Emissions Inspection and Maintenance
Programs
If the vehicle requires an Emissions
Inspection/Maintenance test, the test
equipment will likely connect to the
vehicle's Data Link Connector (DLC).
The DLC is under the instrument panel to
the left of the steering wheel. Connecting
devices that are not used to perform an
Emissions Inspection/Maintenance test or to
service the vehicle may affect vehicle
operation. See Add-On Electrical Equipment
0 252. See your dealer if assistance is
needed.
The vehicle may not pass inspection if:
.The light is on when the engine is
running.
.The light does not come on when the
ignition is in Service Mode.
.Critical emission control systems have not
been completely diagnosed. If this
happens, the vehicle would not be ready
for inspection and might require
several days of routine driving before the
system is ready for inspection. This can
happen if the 12-volt battery has recently
been replaced or run down, or if the
vehicle has been recently serviced.
See your dealer if the vehicle will not pass
or cannot be made ready for the test.
Brake System Warning Light
MetricEnglish
This light should come on briefly when the
vehicle is turned on. If it does not come on
then, have it fixed so it will be ready to
warn you if there is a problem.
If the light comes on and stays on at start
up, there is a brake problem. Have the brake
system inspected right away.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Instruments and Controls 105
SeeTraction Control/Electronic Stability
Control 0213.
Engine Coolant Temperature
Warning Light
This light comes on briefly while starting
the vehicle.
If it does not, have the vehicle serviced by
your dealer. If the system is working
normally the indicator light goes off.
Caution
The engine coolant temperature warning
light indicates that the vehicle has
overheated. Driving with this light on can
damage the engine and it may not be
covered by the vehicle warranty. See
Engine Overheating 0271.
The engine coolant temperature warning
light comes on when the engine has
overheated. If this happens, pull over and turn off the
engine as soon as possible. See
Engine
Overheating 0271.
Tire Pressure Light
For vehicles with the Tire Pressure Monitor
System (TPMS), this light comes on briefly
when the engine is started. It provides
information about tire pressures and
the TPMS.
When the Light Is On Steady
This indicates that one or more of the tires
are significantly underinflated.
A Driver Information Center (DIC) tire
pressure message may also display. Stop as
soon as possible, and inflate the tires to the
pressure value shown on the Tire and
Loading Information label. See Tire Pressure
0 294. When the Light Flashes First and Then Is On
Steady
If the light flashes for about a minute and
then stays on, there may be a problem with
the TPMS. If the problem is not corrected,
the light will come on at every ignition
cycle. See
Tire Pressure Monitor Operation
0 297.
Engine Oil Pressure Light
Oil pressure can vary with engine speed,
outside temperature, and oil viscosity.
On some models, the oil pump will vary
engine oil pressure according to engine
needs. Oil pressure may change quickly as
the engine speed or load varies. This is
normal. If the oil pressure warning light or
Driver Information Center (DIC) message
indicates oil pressure outside the normal
operating range, check the vehicle's oil as
soon as possible.
Caution
Lack of proper engine oil maintenance
can damage the engine. Driving with the
engine oil low can also damage the
engine. The repairs would not be covered
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
106 Instruments and Controls
Caution (Continued)
by the vehicle warranty. Check the oil
level as soon as possible. Add oil if
required, but if the oil level is within the
operating range and the oil pressure is
still low, have the vehicle serviced.
Always follow the maintenance schedule
for changing engine oil.
This light should come on briefly as the
engine is started. If it does not come on,
have the vehicle serviced by your dealer.
If the light comes on and stays on, it means
that oil is not flowing through the engine
properly. The vehicle could be low on oil
and might have some other system
problem. See your dealer.
Low Fuel Warning Light
A Low Fuel Warning Light near the fuel
gauge comes on briefly when the ignition is
turned on as a check to show it is working.
It also comes on when the fuel gauge
indicator nears empty. The light turns off
when fuel is added. If it does not, have the
vehicle serviced.
Security Light
The security light should come on briefly as
the engine is started. If it does not come on,
have the vehicle serviced by your dealer.
If the system is working normally, the
indicator light turns off.If the light stays on and the engine does
not start, there could be a problem with the
theft-deterrent system. See
Immobilizer
Operation 024.
High-Beam On Light
This light comes on when the high-beam
headlamps are in use. See Headlamp High/
Low-Beam Changer 0122.
IntelliBeam Light
This light comes on when the IntelliBeam
system, if equipped, is enabled. See Exterior
Lamp Controls 0121.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
110 Instruments and Controls
Driver Assistance :If equipped, shows
information for Lane Keep Assist (LKA), Lane
Departure Warning (LDW), and Forward
Collision Alert (FCA).
Economy Trend : Shows history of the
Average Fuel Economy from the last 50 km
(30 mi). Each bar represents about 5 km
(3 mi) of driving. During driving the bars will
shift to always reflect the most recent
distance on the right side. Press the
thumbwheel to open the menu while this
display is active to clear the graph. Select
yes or no and press the thumbwheel.
Timer : This display can be used as a timer.
To start the timer, press the thumbwheel to
open the menu while this display is active.
Use
yorzto select Start Timer or Reset.
Press the thumbwheel. To stop the timer,
press the thumbwheel while this display is
active. The display will show the amount of
time that has passed since the timer was
last reset.
Speed Limit : Shows sign information, which
comes from a roadway database in the
onboard navigation, if equipped. The sign
will show “− −”when there is no detected
speed limit or the system is unavailable. Press the thumbwheel while this display is
active to toggle Speed Limit sign on or off.
Speed limit signs in your vehicle display
may vary from actual road speed depending
on the version of your current
navigation map.
Battery Voltage :
Displays the current
battery voltage, if equipped. Battery voltage
changes are normal while driving. See
Charging System Light 0100. If there is a
problem with the battery charging system, a
DIC will display a message.
Oil Pressure : Oil pressure is displayed in
either kilopascal (kPa) or in pounds per
square inch (psi). Oil pressure can vary with
engine speed, outside temperature, and oil
viscosity. On some models, the oil pump will
vary engine oil pressure according to engine
needs. Oil pressure may change quickly as
the engine speed or load varies. This is
normal. If the oil pressure warning light or
DIC message indicates oil pressure outside
the normal operating range, check the
vehicle's oil as soon as possible.
Coolant Temperature : Displays the coolant
temperature in degrees Celsius (°C) or
degrees Fahrenheit (°F).
Driver Information Center (DIC)
(Uplevel)
The DIC displays are shown in the center of
the instrument cluster in the Info app.
See Instrument Cluster (Base and Midlevel)
0 90 or
Instrument Cluster (Uplevel) 093. The
displays show the status of many vehicle
systems.
SorT: Press to move left or right
between the interactive display zones in the
cluster. Press the thumbwheel to select.
yorz: Use the thumbwheel to scroll up
or down in a list. Press the thumbwheel to
select.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
194 Driving and Operating
This affects steering, accelerating, and
braking. Drive at a reduced speed and avoid
sharp turns or abrupt maneuvers.
Traction is reduced on hard packed snow
and ice and it is easy to lose control. Reduce
vehicle speed when driving on hard packed
snow and ice.
{Warning
Driving on frozen lakes, ponds, or rivers
can be dangerous. Ice conditions vary
greatly and the vehicle could fall through
the ice; you and your passengers could
drown. Drive your vehicle on safe
surfaces only.
Driving in Water
{Warning
Driving through rushing water can be
dangerous. Deep water can sweep your
vehicle downstream and you and your
passengers could drown. If it is only
shallow water, it can still wash away the
ground from under your tires. Traction
could be lost, and the vehicle could roll
over. Do not drive through rushing water.
Caution
Do not drive through standing water if it
is deep enough to cover the wheel hubs,
axles, or exhaust pipe. Deep water can
damage the axle and other vehicle parts.
If the standing water is not too deep, drive
through it slowly. At faster speeds, water
can get into the engine and cause it to stall.
Stalling can occur if the exhaust pipe is
under water. Do not turn off the ignition
when driving through water. If the exhaust
pipe is under water, the engine will not
start. When going through water, the brakes
get wet, and it might take longer to stop.
See Driving on Wet Roads 0194.
After Off-Road Driving
Remove any brush or debris that has
collected on the underbody or chassis,
or under the hood. These accumulations can
be a fire hazard.
After operation in mud or sand, have the
brake linings cleaned and checked. These
substances can cause glazing and uneven
braking. Check the body structure, steering,
suspension, wheels, tires, and exhaust
system for damage and check the fuel lines
and cooling system for any leakage. More frequent maintenance service is
required. See
Maintenance Schedule 0332.
Driving on Wet Roads
Rain and wet roads can reduce vehicle
traction and affect your ability to stop and
accelerate. Always drive slower in these
types of driving conditions and avoid driving
through large puddles and deep-standing or
flowing water.
{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
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Driving and Operating 195
Warning (Continued)
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 is wet 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.
SeeTires 0287.
.Turn off cruise control.
.Activate All-Wheel Drive (AWD) mode. See
Driver Mode Control 0214.
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.
{Warning
Coasting downhill in N (Neutral) or with
the ignition off is dangerous. This can
cause overheating of the brakes and loss
of steering assist. Always have the engine
running and the vehicle in gear.
.Drive at speeds that keep the vehicle in
its own lane. Do not swing wide or cross
the center line.
.Be alert on top of hills; something could
be in your lane (e.g., stalled car, crash).
.Pay attention to special road signs (e.g.,
falling rocks area, winding roads, long
grades, passing or no-passing zones) and
take appropriate action.
Winter Driving
Driving on Snow or Ice
Snow or ice between the tires and the road
creates less traction or grip, so drive
carefully. Wet ice can occur at about 0 °C
(32 °F) when freezing rain begins to fall.
Avoid driving on wet ice or in freezing rain
until roads can be treated.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
204 Driving and Operating
may have an internal thermostat in the cord
which will prevent engine heater operation
at temperatures above 0 °F (−18 °C).
{Warning
Do not plug in the engine block heater
while the vehicle is parked in a garage or
under a carport. Property damage or
personal injury may result. Always park
the vehicle in a clear open area away
from buildings or structures.
To Use the Engine Heater
1. Turn off the engine.
2. Check the heater cord for damage. If it isdamaged, 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
(Continued)
Warning (Continued)
or extension cord, could make 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.
The length of time the heater should remain
plugged in depends on several factors. Ask a
dealer in the area where you will be parking
the vehicle for the best advice on this.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
210 Driving and Operating
speed is not reduced within the time
allowed, the lower gear range shift will not
be completed. You must further slow the
vehicle, then press−(Minus) to the desired
lower gear range.
Automatic Engine Grade Braking is not
available when the ERS is active. It is
available in D (Drive) for both normal driving
and Tow/Haul Mode. While using the ERS,
cruise control and the Tow/Haul Mode can
be used. See “Tow/Haul Mode” following.
Tow/Haul Mode
This feature can assist when towing or
hauling a heavy load. See Driver Mode
Control 0214 to activate Tow/Haul Mode.
Drive Systems
All-Wheel Drive
Vehicles with this feature can operate in
All-Wheel Drive (AWD) Mode.
Turn the knob to4to select AWD.
See Driver Mode Control 0214.
When operated in two-wheel drive, the
vehicle will deliver power to the front
wheels only and may provide better fuel
economy.
When using a compact spare tire on an
AWD vehicle, the system automatically
detects the compact spare and reduces AWD
performance to protect the system. To
restore full AWD operation and prevent
excessive wear on the system, replace the
compact spare with a full-size tire as soon as
possible. See Compact Spare Tire 0317.
Brakes
Electric Brake Boost
Vehicles equipped with electric brake boost
have hydraulic brake circuits that are
electronically controlled when the brake
pedal is applied during normal operation.
The system performs routine tests and turns
off within a few minutes after the vehicle is
turned off. Noise may be heard during this
time. If the brake pedal is pressed during
the tests or when the electric brake boost
system is off, a noticeable change in pedal
force and travel may be felt. This is normal.
Antilock Brake System (ABS)
The Antilock Brake System (ABS) helps
prevent a braking skid and maintain steering
while braking hard.
ABS performs a system check when the
vehicle is first driven. A momentary motor
or clicking noise may be heard while this
test is going on, and the brake pedal may
move slightly. This is normal.