ignition CHEVROLET BLAZER 2021 Workshop Manual

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
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-
14608203) - 2021 - CRC - 10/29/20
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

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Vehicle Care 297
When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as
intended. TPMS malfunctions may occur for
a variety of reasons, including the
installation of replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on
your vehicle to ensure that the replacement
or alternate tires and wheels allow the
TPMS to continue to function properly.
SeeTire Pressure Monitor Operation 0297.
See Radio Frequency Statement 0357.
Tire Pressure Monitor Operation
This vehicle may have a Tire Pressure
Monitor System (TPMS). The TPMS is
designed to warn the driver when a low tire
pressure condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire and
wheel assembly. The TPMS sensors monitor
the air pressure in the tires and transmit the
tire pressure readings to a receiver located
in the vehicle.
When a low tire pressure condition is
detected, the TPMS illuminates the low tire
pressure warning light located on the
instrument cluster. If the warning light
comes on, stop as soon as possible and
inflate the tires to the recommended
pressure shown on the Tire and Loading
Information label. See Vehicle Load Limits
0 197.
A message to check the pressure in a
specific tire displays in the Driver
Information Center (DIC). The low tire
pressure warning light and the DIC warning
message come on at each ignition cycle
until the tires are inflated to the correct
inflation pressure. Using the DIC, tire
pressure levels can be viewed. For additional
information and details about the DIC
operation and displays see Driver
Information Center (DIC) (Base and Midlevel)
0 107 or
Driver Information Center (DIC) (Uplevel)
0 110. The low tire pressure warning light may
come on in cool weather when the vehicle is
first started, and then turn off as the vehicle
is driven. This could be an early indicator
that the air pressure is getting low and
needs to be inflated to the proper pressure.
A Tire and Loading Information label,
attached to your vehicle, shows the size of
the original equipment tires and the correct
inflation pressure for the tires when they
are cold. See
Vehicle Load Limits 0197, for
an example of the Tire and Loading
Information label and its location. Also see
Tire Pressure 0294.
The TPMS can warn about a low tire
pressure condition but it does not replace
normal tire maintenance. See Tire Inspection
0 300, Tire Rotation 0300 and
Tires 0287.
Caution
Tire sealant materials are not all the
same. A non-approved tire sealant could
damage the TPMS sensors. TPMS sensor
damage caused by using an incorrect tire
sealant is not covered by the vehicle
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
298 Vehicle Care
Caution (Continued)
warranty. Always use only the GM
approved tire sealant available through
your dealer or included in the vehicle.
Factory-installed Tire Inflator Kits use a
GM-approved liquid tire sealant. Using
non-approved tire sealants could damage the
TPMS sensors. See Tire Sealant and
Compressor Kit 0307 for information
regarding the inflator kit materials and
instructions.
TPMS Malfunction Light and Message
The TPMS will not function properly if one
or more of the TPMS sensors are missing or
inoperable. When the system detects a
malfunction, the low tire pressure warning
light flashes for about one minute and then
stays on for the remainder of the ignition
cycle. A DIC warning message also displays.
The malfunction light and DIC warning
message come on at each ignition cycle
until the problem is corrected. Some of the
conditions that can cause these to come
on are:
.One of the road tires has been replaced
with the spare tire. The spare tire does
not have a TPMS sensor. The malfunction light and DIC message should go off after
the road tire is replaced and the sensor
matching process is performed
successfully. See
“TPMS Sensor Matching
Process” later in this section.
.The TPMS sensor matching process was
not done or not completed successfully
after rotating the tires. The malfunction
light and the DIC message should go off
after successfully completing the sensor
matching process. See "TPMS Sensor
Matching Process" later in this section.
.One or more TPMS sensors are missing or
damaged. The malfunction light and the
DIC message should go off when the
TPMS sensors are installed and the sensor
matching process is performed
successfully. See your dealer for service.
.Replacement tires or wheels do not match
the original equipment tires or wheels.
Tires and wheels other than those
recommended could prevent the TPMS
from functioning properly. See Buying
New Tires 0302.
.Operating electronic devices or being near
facilities using radio wave frequencies
similar to the TPMS could cause the TPMS
sensors to malfunction. If the TPMS is not functioning properly it
cannot detect or signal a low tire pressure
condition. See your dealer for service if the
TPMS malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and audible
alerts outside the vehicle to help when
inflating an underinflated tire to the
recommended cold tire pressure.
When the low tire pressure warning light
comes on:
1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal lamp will flash.
When the recommended pressure is
reached, the horn sounds once and the
turn signal lamp will stop flashing and
briefly turn solid.
Repeat these steps for all underinflated tires
that have illuminated the low tire pressure
warning light.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Vehicle Care 299
{Warning
Overinflating a tire could cause the tire
to rupture and you or others could be
injured. Do not exceed the maximum
pressure listed on the tire sidewall. See
Tire Sidewall Labeling0289 and
Vehicle Load Limits 0197.
If the tire is overinflated by more than
35 kPa (5 psi), the horn will sound multiple
times and the turn signal lamp will continue
to flash for several seconds after filling
stops. To release and correct the pressure,
while the turn signal lamp is still flashing,
briefly press the center of the valve stem.
When the recommended pressure is reached,
the horn sounds once.
If the turn signal lamp does not flash within
15 seconds after starting to inflate the tire,
the tire fill alert has not been activated or is
not working.
If the hazard warning flashers are on, the
tire fill alert visual feedback will not work
properly.
The TPMS will not activate the tire fill alert
properly under the following conditions:
.There is interference from an external
device or transmitter.
.The air pressure from the inflation device
is not sufficient to inflate the tire.
.There is a malfunction in the TPMS.
.There is a malfunction in the horn or turn
signal lamps.
.The identification code of the TPMS
sensor is not registered to the system.
.The battery of the TPMS sensor is low.
If the tire fill alert does not operate due to
TPMS interference, move the vehicle about
1 m (3 ft) back or forward and try again.
If the tire fill alert feature is not working,
use a tire pressure gauge.
TPMS Sensor Matching Process
Each TPMS sensor has a unique
identification code. The identification code
needs to be matched to a new tire/wheel
position after rotating the vehicle’s tires or
replacing one or more of the TPMS sensors.
The TPMS sensor matching process should
also be performed after replacing a spare
tire with a road tire containing the TPMS
sensor. The malfunction light and the DIC
message should go off at the next ignition
cycle. The sensors are matched to the tire/
wheel positions, using a TPMS relearn tool, in the following order: driver side front tire,
passenger side front tire, passenger side rear
tire, and driver side rear tire. See your
dealer for service or to purchase a relearn
tool. A TPMS relearn tool can also be
purchased. See Tire Pressure Monitor Sensor
Activation Tool at
www.gmtoolsandequipment.com or call
1-800-GM TOOLS (1-800-468-6657).
There are two minutes to match the first
tire/wheel position, and five minutes overall
to match all four tire/wheel positions. If it
takes longer, the matching process stops
and must be restarted.
The TPMS sensor matching process is:
1. Set the parking brake.
2. Place the vehicle in Service Mode. See Ignition Positions 0200.
3. Make sure the Tire Pressure info page option is turned on. The info pages on
the DIC can be turned on and off
through the Options menu. See Driver
Information Center (DIC) (Base and
Midlevel) 0107 or
Driver Information Center (DIC) (Uplevel)
0 110.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
Vehicle Care 319
1. Discharged Battery Positive (+)Terminal
2. Discharged Battery Remote Negative (–) Terminal
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
0 205.
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.
{Warning
Fans or other moving engine parts can
injure you badly. Keep your hands away
from moving parts once the engine is
running.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
OnStar 361
.Receive a Diagnostic check of the vehicle's
key operating systems.
.Receive Roadside Assistance.
.Manage Wi-Fi Settings, if equipped.
Press
>to get a priority connection to an
OnStar Advisor available 24/7 to:
.Get help for an emergency.
.Be a Good Samaritan or respond to an
AMBER Alert.
.Get assistance in severe weather or other
crisis situations and find evacuation
routes.
OnStar Services
Emergency
Emergency Services require an active safety
and security plan. With Automatic Crash
Response, built-in sensors can automatically
alert a specially trained OnStar Advisor who
is immediately connected in to the vehicle
to help.
Press
>for a priority connection to an
OnStar Advisor who can contact emergency
service providers, direct them to your exact
location, and relay important information. With OnStar Crisis Assist, specially trained
Advisors are available 24 hours a day, 7 days
a week, to provide a central point of
contact, assistance, and information during a
crisis.
With Roadside Assistance, Advisors can
locate a nearby service provider to help with
a flat tire, a battery jump, or an empty
gas tank.
Security
If equipped, OnStar provides these services:
.With Stolen Vehicle Assistance, OnStar
Advisors can use GPS to pinpoint the
vehicle and help authorities quickly
recover it.
.With Remote Ignition Block, if equipped,
OnStar can block the engine from being
restarted.
.With Stolen Vehicle Slowdown,
if equipped, OnStar can work with law
enforcement to gradually slow the
vehicle down.
Theft Alarm Notification
If equipped, if the doors are locked and the
vehicle alarm sounds, a notification by text,
e-mail, or phone call will be sent. If the
vehicle is stolen, an OnStar Advisor can work
with authorities to recover the vehicle.
OnStar Additional
Information
In-Vehicle Audio Messages
Audio messages may play important
information at the following times:
.Prior to vehicle purchase. PressQto set
up an account.
.After change in ownership and at
90 days.
Transferring Service
PressQto request account transfer
eligibility information. The Advisor can
cancel or change account information.
Selling/Transferring the Vehicle
Call 1-888-4ONSTAR (1-888-466-7827)
immediately to terminate your OnStar or
connected services if the vehicle is disposed
of, sold, transferred, or if the lease ends.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
OnStar 363
Languages
The vehicle can be programmed to respond
in multiple languages. Press
Qand ask for
an Advisor. Advisors are available in English,
Spanish, and French. Available languages
may vary by country.
Potential Issues
OnStar cannot perform Remote Door Unlock
or Stolen Vehicle Assistance after the vehicle
has been off continuously for 10 days
without an ignition cycle. If the vehicle has
not been started for 10 days, OnStar can
contact Roadside Assistance or a locksmith
to help gain access to the vehicle.
Global Positioning System (GPS)
.Obstruction of the GPS can occur in a
large city with tall buildings; in parking
garages; around airports; in tunnels and
underpasses; or in an area with very
dense trees. If GPS signals are not
available, the OnStar system should still
operate to call OnStar. However, OnStar
could have difficulty identifying the exact
location.
.In emergency situations, OnStar can use
the last stored GPS location to send to
emergency responders. A temporary loss of GPS can cause loss of
the ability to send a Turn-by-Turn
Navigation route. The Advisor may give a
verbal route or may ask for a call back after
the vehicle is driven into an open area.
Cellular and GPS Antennas
Cellular reception is required for OnStar to
send remote signals to the vehicle. Do not
place items over or near the antenna to
prevent blocking cellular and GPS signal
reception.
Unable to Connect to OnStar Message
If there is limited cellular coverage or the
cellular network has reached maximum
capacity, this message may come on. Press
Qto try the call again or try again after
driving a few miles into another
cellular area.
Vehicle and Power Issues
OnStar services require a vehicle electrical
system, wireless service, and GPS satellite
technologies to be available and operating
for features to function properly. These
systems may not operate if the battery is
discharged or disconnected.
Add-on Electrical Equipment
The OnStar system is integrated into the
electrical architecture of the vehicle. Do not
add any electrical equipment. See Add-On
Electrical Equipment 0252. Added electrical
equipment may interfere with the operation
of the OnStar system and cause it to not
operate.
Vehicle Software Updates
OnStar or GM may remotely deliver
software updates or changes to the vehicle
without further notice or consent. These
updates or changes may enhance or
maintain safety, security, or the operation
of the vehicle or the vehicle systems.
Software updates or changes may affect or
erase data or settings that are stored in the
vehicle, such as saved navigation
destinations or pre-set radio stations.
Neither OnStar nor GM is responsible for
any affected or erased data or settings.
These updates or changes may also collect
personal information. Such collection is
described in the OnStar privacy statement or
separately disclosed at the time of
installation. These updates or changes may
also cause a system to automatically
communicate with GM servers to collect
information about vehicle system status,

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14608203) - 2021 - CRC - 10/29/20
372 Index
Fuses (cont'd)Instrument Panel Fuse Block . . . . . . . . . . . 284
Rear Compartment Fuse Block . . . . . . . . . 285
G
Garage Door Opener . . . . . . . . . . . . . . . . . . . . . . 117
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
Gauges
Engine Coolant Temperature . . . . . . . . . . . . 96
Engine Oil Temperature . . . . . . . . . . . . . . . . . 96
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Voltmeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Warning Lights and Indicators . . . . . . . . . . 89
General Information Service and Maintenance . . . . . . . . . . . . . . 331
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
Vehicle Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
Global Positioning System (GPS) . . . . . . . . . . 152
Glove Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Guidance Problems with the Route . . . . . . . . . . . . . . 153
H
Hazard Warning Flashers . . . . . . . . . . . . . . . . .124
HD Radio Technology . . . . . . . . . . . . . . . . . . . . . 135
Head Restraints . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . 278
Daytime Running Lamps (DRL) . . . . . . . . . 123
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
High Intensity Discharge (HID)Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
High-Beam On Light . . . . . . . . . . . . . . . . . . . 106
High/Low Beam Changer . . . . . . . . . . . . . . 122
Lamps On Reminder . . . . . . . . . . . . . . . . . . . 107
Heated Rear Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . . 83
Heated and Ventilated Front Seats . . . . . . . 40
Heated Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Heater
Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182
High Voltage Devices and Wiring . . . . . . . . 279
High-Beam On Light . . . . . . . . . . . . . . . . . . . . . 106
High-Speed Operation . . . . . . . . . . . . . . . . . . . 295
Hill and Mountain Roads . . . . . . . . . . . . . . . . 195
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . . . . . 212 Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
Hooks
Shopping Bag . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
How to Wear Seat Belts Properly . . . . . . . . . 45
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .182
I
If the System Needs Service . . . . . . . . . . . . . . 153
Ignition Positions . . . . . . . . . . . . . . . . . . . . . . . . 200
Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Indicator Pedestrian Ahead . . . . . . . . . . . . . . . . . . . . . . 104
Vehicle Ahead . . . . . . . . . . . . . . . . . . . . . . . . . 103
Infants and Young Children, Restraints . . . . .61
Information Publication Ordering . . . . . . . . . . . . . . . . . . . 356
Infotainment System . . . . . . . . . . . . . . . . . . . . 359
Instrument Cluster . . . . . . . . . . . . . . . . . . . . 90, 93
Instrument Panel Overview . . . . . . . . . . . . . . . . 4
Interior Rearview Mirrors . . . . . . . . . . . . . . . . . 26
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 1, 128
J
Jump Starting - North America . . . . . . . . . . . .318
K
Keyless Entry Remote (RKE) System . . . . . . . . . . . . . . . . . . . . 7