2021 CHEVROLET BLAZER brake

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
250 Driving and Operating
attempt to tap into your vehicle's hydraulic
brake system. If you do, both the vehicle
antilock brakes and the trailer brakes may
not function, which could result in a crash.
Trailer Wiring Harness
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin
connector, is at the rear of the vehicle and
is tied to the vehicle's frame. The harness
requires the installation of a trailer
connector, which is available through your
dealer.
Use only a round, seven-wire connector with
flat blade terminals meeting SAE J2863
specifications for proper electrical
connectivity.
The seven-wire harness contains the
following trailer circuits:
.Yellow: Left Stop/Turn Signal
.Green: Right Stop/Turn Signal
.Brown: Tail/Parking Lamps
.White: Trailer Ground
.Red: Stop Lamp Supply Voltage
.Black: Back Up Lamp Supply Voltage
.Blue: Service BrakesThe fuse for the electric trailer brake circuit
is in the engine compartment fuse block,
but the wires may not be connected. They
should be connected by your dealer or a
qualified service center. To control electric
trailer brakes, a trailer brake controller needs
to be installed on the vehicle by your dealer
or a qualified service center. See electric
brake control wiring provisions.
If a battery outside the vehicle is being
charged, place the vehicle in Tow/Haul
Mode. This will boost the vehicle system
voltage and properly charge the battery.
If the trailer is too light for Tow/Haul Mode,
turn on the non-HID only headlamps as a
second way to boost the vehicle system
voltage and charge the battery.
Electric Trailer Brake Control Wiring
Provisions
Wiring provisions for an aftermarket electric
trailer brake controller are included with the
vehicle as part of the trailer wiring package.
The harness contains the following circuits:
These wiring provisions for an electric trailer
brake controller are included with the
vehicle as part of the trailer wiring package.
The body harness, inside the front driver
side instrument panel, contains blunt cut wires below the headlamp switch for the
electric trailer brake controller. The harness
contains the following wires:
.Blue: Electric Trailer Brakes
.Blue: Battery Feed
.White/Blue: Brake Apply Signal
.Black: Ground
Refer to the aftermarket electric trailer brake
controller owner's manual to determine wire
color coding of the electric trailer brake
controller. The wire colors on the brake
controller may be different from the vehicle.
The electric trailer brake controller should be
installed by your dealer or a qualified
service center.
Trailer Lamps
Always check all trailer lamps are working at
the beginning of each trip, and periodically
on longer trips.
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals will illuminate to indicate the vehicle
is turning, changing lanes, or stopping.
When towing a trailer, the arrows on the
instrument cluster will illuminate even if the
trailer is not properly connected or the bulbs
are burned out.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Driving and Operating 251
Tow/Haul Mode
For instructions on how to enter Tow/Haul
Mode, seeDriver Mode Control 0214.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load. See Tow/
Haul Mode 0210.
Tow/Haul Mode is designed to be most
effective when the vehicle and trailer
combined weight is at least 75% of the
vehicle's Gross Combined Weight Rating
(GCWR). See “Weight of the Trailer” under
Trailer Towing 0245. Tow/Haul Mode is
most useful when towing a heavy trailer or
carrying a large or heavy load:
.Through rolling terrain.
.In stop-and-go traffic.
.In busy parking lots.
Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and 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 Control 0213.
{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 cargo, improper trailer hitch
configuration, or improperly inflated or
incorrect vehicle or trailer tires. See
Towing Equipment 0248 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.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Vehicle Care 253
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 254
California Proposition 65 Warning . . . . . 254
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 254
Accessories and Modifications . . . . . . . . . 254
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 255
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
Engine Compartment Overview . . . . . . . . 257
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
Engine Oil Life System . . . . . . . . . . . . . . . . 264
Automatic Transmission Fluid . . . . . . . . . 265
Engine Air Filter Life System . . . . . . . . . . 265
Engine Air Cleaner/Filter . . . . . . . . . . . . . . 265
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 267
Engine Overheating . . . . . . . . . . . . . . . . . . . . 271
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Battery - North America . . . . . . . . . . . . . . . 274
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . 275
Automatic Transmission Shift Lock Control Function Check . . . . . . . . . . . . . . 275
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
Wiper Blade Replacement . . . . . . . . . . . . . 276 Windshield Replacement . . . . . . . . . . . . . . . 277
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 278
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 278
High Intensity Discharge (HID)
Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Back-Up Lamps . . . . . . . . . . . . . . . . . . . . . . . . 278
Electrical System
High Voltage Devices and Wiring . . . . . . 279
Electrical System Overload . . . . . . . . . . . . 279
Fuses and Circuit Breakers . . . . . . . . . . . . 280
Engine Compartment Fuse Block . . . . . . 280
Instrument Panel Fuse Block . . . . . . . . . . 284
Rear Compartment Fuse Block . . . . . . . . . 285
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . 288
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
Summer Tires . . . . . . . . . . . . . . . . . . . . . . . . . 289
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 289
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 291
Tire Terminology and Definitions . . . . . . 292
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 Tire Pressure Monitor System . . . . . . . . . 296
Tire Pressure Monitor Operation . . . . . . 297
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 300
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 300
When It Is Time for New Tires . . . . . . . . 301
Buying New Tires . . . . . . . . . . . . . . . . . . . . . 302
Different Size Tires and Wheels . . . . . . . 303
Uniform Tire Quality Grading . . . . . . . . . 303
Wheel Alignment and Tire Balance . . . . 305
Wheel Replacement . . . . . . . . . . . . . . . . . . . 305
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 306
Tire Sealant and Compressor Kit . . . . . . . 307
Storing the Tire Sealant and
Compressor Kit . . . . . . . . . . . . . . . . . . . . . . . 313
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . . 313
Compact Spare Tire . . . . . . . . . . . . . . . . . . . . 317
Jump Starting
Jump Starting - North America . . . . . . . . 318
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . . 320
Recreational Vehicle Towing . . . . . . . . . . . 321
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
254 Vehicle Care
General Information
For service and parts needs, visit your
dealer. You will receive genuine GM parts
and GM-trained and supported service
people.
Genuine GM parts have one of these marks:
California Proposition 65 Warning
{Warning
Most motor vehicles, including this one,
as well as many of its service parts and
fluids, contain and/or emit chemicals
known to the State of California to cause(Continued)
Warning (Continued)
cancer and birth defects or other
reproductive harm. Engine exhaust, many
parts and systems, many fluids, and
some component wear by-products
contain and/or emit these chemicals. For
more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0274 and
Jump Starting - North America 0318 and the
back cover.
California Perchlorate Materials
Requirements
Certain types of automotive applications,
such as airbag initiators, seat belt
pretensioners, and lithium batteries
contained in electronic keys, may contain
perchlorate materials. Perchlorate Material –
special handling may apply. See
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and Modifications
Adding non-dealer accessories or making
modifications to the vehicle can affect
vehicle performance and safety, including
such things as airbags, braking, stability,
ride and handling, emissions systems,
aerodynamics, durability, and electronic
systems like antilock brakes, traction control,
and stability control. These accessories or
modifications could even cause malfunction
or damage not covered by the vehicle
warranty.
Damage to suspension components caused
by modifying vehicle height outside of
factory settings will not be covered by the
vehicle warranty.
Damage to vehicle components resulting
from modifications or the installation or use
of non-GM certified parts, including control
module or software modifications, is not
covered under the terms of the vehicle
warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement
and function with other systems on the
vehicle. See your dealer to accessorize the
vehicle using genuine GM Accessories
installed by a dealer technician.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
258 Vehicle Care
1.Engine Air Cleaner/Filter 0265.
2. Engine Oil Fill Cap. See Engine Oil0262.
3. Engine Oil Dipstick. See Engine Oil0262.
4. Engine Cooling Fan (Out of View). See Cooling System 0267.
5. Brake Fluid Reservoir. See Brake Fluid
0 273.
6. Battery - North America 0274.
7. Engine Coolant Surge Tank and Pressure Cap. See Cooling System 0267.
8. Positive (+) Battery Terminal (Under Cover). See Jump Starting - North
America 0318.
9. Windshield Washer Fluid Reservoir. See Washer Fluid 0272.
10. Engine Compartment Fuse Block 0280.
11. Remote Negative (-) Battery Terminal. SeeJump Starting - North America 0318.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
260 Vehicle Care
1.Engine Air Cleaner/Filter 0265.
2. Engine Oil Fill Cap. See Engine Oil0262.
3. Engine Oil Dipstick. See Engine Oil0262.
4. Engine Cooling Fan (Out of View). See Cooling System 0267.
5. Brake Fluid Reservoir. See Brake Fluid
0 273.
6. Battery - North America 0274.
7. Engine Coolant Surge Tank and Pressure Cap. See Cooling System 0267.
8. Positive (+) Battery Terminal (Under Cover). See Jump Starting - North
America 0318.
9. Windshield Washer Fluid Reservoir. See Washer Fluid 0272.
10. Engine Compartment Fuse Block 0280.
11. Remote Negative (-) Battery Terminal. SeeJump Starting - North America 0318.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 261
3.6L V6 Engine
1. Engine Air Cleaner/Filter 0265.
2. Engine Oil Fill Cap. See Engine Oil0262.
3. Engine Oil Dipstick. See Engine Oil0262.
4. Engine Cooling Fan (Out of View). See Cooling System 0267. 5. Brake Fluid Reservoir. See
Brake Fluid
0 273.
6. Battery - North America 0274.
7. Engine Coolant Surge Tank and Pressure Cap. See Cooling System 0267. 8. Positive (+) Battery Terminal. See
Jump
Starting - North America 0318.
9. Windshield Washer Fluid Reservoir. See Washer Fluid 0272.
10. Engine Compartment Fuse Block 0280.

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)