ECU CHEVROLET TRAILBLAZER 2021 Workshop Manual

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
14400528) - 2021 - CRC - 11/7/19
306 Vehicle Care
1. Position the vehicle to tow and thensecure it to the tow vehicle.
2. Apply the parking brake.
3. Put the vehicle into ACC/ACCESSORY by pressing ENGINE START/STOP one time
without the brake pedal applied.
4. Shift the transmission to N (Neutral). The chime will ring continuously for
30 seconds. Leave the transmission in
N (Neutral).
5. Release the parking brake.
6. Disconnect the negative battery cable at the battery. See “Negative Battery Cable
Disconnection” underBattery - North
America 0261.
7. Cover the negative battery post with a non-conductive material to prevent any
contact with the negative battery
terminal.
Caution
If 113 km/h (70 mph) is exceeded while
towing the vehicle, it could be damaged.
Never exceed 113 km/h (70 mph) while
towing the vehicle.
To disconnect the towed vehicle: 1. Park on a level surface. 2. Apply the parking brake.
3. Make sure that the ignition is off.
4. Remove any tape, glue, or excess
material from the negative battery post.
5. Connect the battery. See “Negative
Battery Cable Reconnection” under
Battery - North America 0261.
6. Disconnect the vehicle from the tow vehicle.
7. Release the parking brake.
Dolly Towing (All-Wheel-Drive Vehicles)
All-wheel-drive vehicles must not be towed
with two wheels on the ground.
Dolly Towing (Front-Wheel-Drive
Vehicles Only)
To tow a front-wheel-drive vehicle from the
front with two wheels on the ground: 1. Put the front wheels on a dolly.
2. Move the shift lever to P (Park).
3. Set the parking brake.
4. Clamp the steering wheel in a straight-ahead position with a clamping
device designed for towing.
5. Turn the vehicle off.
6. Secure the vehicle to the dolly.
7. Release the parking brake.

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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314 Vehicle Care
Warning (Continued)
rinse seat belt webbing only with mild
soap and lukewarm water. Allow the
webbing to dry.
Floor Mats
{Warning
If a floor mat is the wrong size or is not
properly installed, it can interfere with
the pedals. Interference with the pedals
can cause unintended acceleration and/or
increased stopping distance which can
cause a crash and injury. Make sure the
floor mat does not interfere with the
pedals.
Use the following guidelines for proper floor
mat usage.
.The original equipment floor mats were
designed for your vehicle. If the floor
mats need replacing, it is recommended
that GM certified floor mats be
purchased. Non-GM floor mats may not
fit properly and may interfere with the
accelerator or brake pedal. Always check
that the floor mats do not interfere with
the pedals.
.Do not use a floor mat if the vehicle is
not equipped with a floor mat retainer on
the driver side floor.
.Use the floor mat with the correct side
up. Do not turn it over.
.Do not place anything on top of the
driver side floor mat.
.Use only a single floor mat on the
driver side.
.Do not place one floor mat on top of
another.
The driver side floor mat is held in place by
a button-type retainer.
Removing and Replacing the Floor Mats 1. Pull up on the rear of the floor mat to unlock the retainers and remove. 2. Reinstall by lining up the floor mat
retainer openings over the carpet
retainers and snap into position.
3. Make sure the floor mat is properly secured in place. Verify the floor mat
does not interfere with the pedals.

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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332 Customer Information
Customer Information
Customer Information
Customer Satisfaction Procedure . . . . . . . 332
Customer Assistance Offices . . . . . . . . . . . 334
Customer Assistance for Text Telephone(TTY) Users . . . . . . . . . . . . . . . . . . . . . . . . . . 334
Online Owner Center . . . . . . . . . . . . . . . . . . 334
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
Roadside Assistance Program . . . . . . . . . . 335
Scheduling Service Appointments . . . . . . 336
Courtesy Transportation Program . . . . . . 337
Collision Damage Repair . . . . . . . . . . . . . . . 337
Publication Ordering Information . . . . . . 339
Radio Frequency Statement . . . . . . . . . . . 340
Reporting Safety Defects
Reporting Safety Defects to the United States Government . . . . . . . . . . . . . . . . . . 340
Reporting Safety Defects to the Canadian Government . . . . . . . . . . . . . . . 340
Reporting Safety Defects to General Motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
Vehicle Data Recording and Privacy
Vehicle Data Recording and Privacy . . . . 341
Cybersecurity . . . . . . . . . . . . . . . . . . . . . . . . . . 341
Event Data Recorders . . . . . . . . . . . . . . . . . . 342
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342
Infotainment System . . . . . . . . . . . . . . . . . . 342Customer Information
Customer Satisfaction Procedure
Your satisfaction and goodwill are important
to your dealer and to Chevrolet. Normally,
any concerns with the sales transaction or
the operation of the vehicle will be resolved
by your dealer's sales or service
departments. Sometimes, however, despite
the best intentions of all concerned,
misunderstandings can occur. If your concern
has not been resolved to your satisfaction,
the following steps should be taken:
STEP ONE : Discuss your concern with a
member of dealership management.
Normally, concerns can be quickly resolved
at that level. If the matter has already been
reviewed with the sales, service, or parts
manager, contact the owner of your
dealership or the general manager.
STEP TWO : If after contacting a member of
dealership management, it appears your
concern cannot be resolved by your
dealership without further help, in the U.S.,
call the Chevrolet Customer Assistance
Center at 1-800-222-1020. In Canada, call
General Motors of Canada Customer Care
Centre at 1-800-263-3777 (English),
or 1-800-263-7854 (French).

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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336 Customer Information
.Lock-Out Service:Service to unlock the
vehicle if you are locked out. A remote
unlock may be available if you have
OnStar. For security reasons, the driver
must present identification before this
service is given.
.Emergency Tow from a Public Road or
Highway: Tow to the nearest Chevrolet
dealer for warranty service, or if the
vehicle was in a crash and cannot be
driven. Assistance is not given when the
vehicle is stuck in the sand, mud,
or snow.
.Flat Tire Change: Service to change a flat
tire with the spare tire. The spare tire,
if equipped, must be in good condition
and properly inflated. It is the owner's
responsibility for the repair or
replacement of the tire if it is not covered
by the warranty.
.Battery Jump Start: Service to jump start
a dead battery.
.Trip Interruption Benefits and Assistance:
If your trip is interrupted due to a
warranty event, incidental expenses may
be reimbursed within the Powertrain
warranty period. Items considered are
reasonable and customary hotel, meals,
rental car, or a vehicle being delivered
back to the customer, up to 500 miles.
Services Not Included in Roadside
Assistance
.Impound towing caused by violation of
any laws
.Legal fines
.Mounting, dismounting, or changing of
snow tires, chains, or other traction
devices
Service is not provided if a vehicle is in an
area that is not accessible to the service
vehicle or is not a regularly traveled or
maintained public road, which includes ice
and winter roads. Off-road use is not
covered.
Services Specific to Canadian-Purchased
Vehicles
.Fuel Delivery: Reimbursement is up to
7 liters. If available, diesel fuel delivery
may be restricted. Propane and other
fuels are not provided through this
service.
.Lock-Out Service: Vehicle registration is
required.
.Trip Interruption Benefits and Assistance:
Must be over 150 km from where your
trip was started to qualify.
Pre-authorization, original detailed
receipts, and a copy of the repair orders are required. Once authorization has been
received, the Roadside Assistance advisor
will help to make arrangements and
explain how to receive payment.
.Alternative Service:
If assistance cannot
be provided right away, the Roadside
Assistance advisor may give permission to
get local emergency road service. You will
receive payment, up to $100, after
sending the original receipt to Roadside
Assistance. Mechanical failures may be
covered, however any cost for parts and
labor for repairs not covered by the
warranty are the owner responsibility.
Scheduling Service Appointments
When the vehicle requires warranty service,
contact your dealer and request an
appointment. By scheduling a service
appointment and advising the service
consultant of your transportation needs,
your dealer can help minimize your
inconvenience.
If the vehicle cannot be scheduled into the
service department immediately, keep
driving it until it can be scheduled for
service, unless, of course, the problem is

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Customer Information 341
Transport Canada
Motor Vehicle Safety Directorate
Defect Investigations and Recalls
Division
80 Noel Street
Gatineau
,QC J8Z 0A1
Reporting Safety Defects to
General Motors
In addition to notifying NHTSA (or Transport
Canada) in a situation like this, notify
General Motors.
In the U.S., call 1-800-222-1020, or write:
Chevrolet Motor Division
Chevrolet Customer Assistance Center
P.O. Box 33170
Detroit, MI 48232-5170
In Canada, call 1-800-263-3777 (English) or
1-800-263-7854 (French), or write:
General Motors of Canada Company
Customer Care Centre, Mail Code:
CA1-163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
In Mexico, call 800-466-0811 or
800-508-0000.In other Central America and Caribbean
Countries, call 52-555-901-2369.
Vehicle Data Recording and
Privacy
The vehicle has a number of computers that
record information about the vehicle’s
performance and how it is driven or used.
For example, the vehicle uses computer
modules to monitor and control engine and
transmission performance, to monitor the
conditions for airbag deployment and
deploy them in a crash, and, if equipped, to
provide antilock braking to help the driver
control the vehicle. These modules may
store data to help the dealer technician
service the vehicle or to help GM improve
safety or features. Some modules may also
store data about how the vehicle is
operated, such as rate of fuel consumption
or average speed. These modules may retain
personal preferences, such as radio presets,
seat positions, and temperature settings.
Cybersecurity
GM collects information about the use of
your vehicle including operational and safety
related information. We collect thisinformation to provide, evaluate, improve,
and troubleshoot our products and services
and to develop new products and services.
The protection of vehicle electronics systems
and customer data from unauthorized
outside electronic access or control is
important to GM. GM maintains appropriate
security standards, practices, guidelines and
controls aimed at defending the vehicle and
the vehicle service ecosystem against
unauthorized electronic access, detecting
possible malicious activity in related
networks, and responding to suspected
cybersecurity incidents in a timely,
coordinated and effective manner. Security
incidents could impact your safety or
compromise your private data. To minimize
security risks, please do not connect your
vehicle electronic systems to unauthorized
devices or connect your vehicle to any
unknown or untrusted networks (such as
Bluetooth, WIFI or similar technology). In
the event you suspect any security incident
impacting your data or the safe operation of
your vehicle, please stop operating your
vehicle and contact your dealer.

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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OnStar 343
OnStar
OnStar Overview
OnStar Overview . . . . . . . . . . . . . . . . . . . . . . 343
OnStar Services
Emergency . . . . . . . . . . . . . . . . . . . . . . . . . . . . 344
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 344
OnStar Additional Information
OnStar Additional Information . . . . . . . . 344
OnStar Overview
=Voice Command Button
QBlue OnStar Button
>Red Emergency Button
This vehicle may be equipped with a
comprehensive, in-vehicle system that can
connect to an OnStar Advisor for Emergency,
Security, Navigation, Connections, and
Diagnostics Services. OnStar services may
require a paid service plan and data plan.
OnStar requires the vehicle battery and
electrical system, cellular service, and GPS
satellite signals to be available and
operating. OnStar acts as a link to existing
emergency service providers. OnStar may
collect information about you and your
vehicle, including location information. See
OnStar User Terms, Privacy Statement, and
Software Terms for more details including
system limitations at www.onstar.com (U.S.)
or www.onstar.ca (Canada). The OnStar system status light is next to
the OnStar buttons. If the status light is:
.Solid Green: System is ready.
.Flashing Green: On a call.
.Red: Indicates a problem.
.Off: System is off. PressQtwice to
speak with an OnStar Advisor.
Press
Qor call 1-888-4ONSTAR
(1-888-466-7827) to speak to an Advisor.
Functionality of the Voice Command button
may vary by vehicle and region.
Press
=to:
.Open the OnStar app on the infotainment
display. See OnStar System 0133.
Or
.Give OnStar Turn-by-Turn Navigation voice
commands.
.Obtain and customize the Wi-Fi hotspot
name or SSID and password, if equipped.
Press
Qto connect to an Advisor to:
.Verify account information or update
contact information.
.Get driving directions.
.Receive a Diagnostic check of the vehicle's
key operating systems.

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344 OnStar
.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.

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346 OnStar
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 0241. 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 Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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Connected Services 349
PressQ, then ask the Advisor to download
directions to the vehicle’s navigation system,
if equipped. After the call ends, the
navigation screen will provide prompts to
begin driving directions. Routes that are sent
to the navigation screen can only be
canceled through the navigation system.
See www.onstar.com (U.S.) or www.onstar.ca
(Canada).
Connections
The following services help with staying
connected.
For coverage maps, see www.onstar.com
(U.S.) or www.onstar.ca (Canada).
Ensuring Security
.Change the default passwords for the
Wi-Fi hotspot and myChevrolet mobile
application. Make these passwords
different from each other and use a
combination of letters and numbers to
increase the security.
.Change the default name of the SSID
(Service Set Identifier). This is your
network’s name that is visible to other
wireless devices. Choose a unique name
and avoid family names or vehicle
descriptions. Wi-Fi Hotspot (If Equipped)
The vehicle may have a built-in Wi-Fi
hotspot that provides access to the Internet
and web content at 4G LTE speed. Up to
seven mobile devices can be connected.
A data plan is required. Use the in-vehicle
controls only when it is safe to do so.
1. To retrieve Wi-Fi hotspot information, press
=to open the OnStar app on the
infotainment display, then select Wi-Fi
Hotspot. On some vehicles, touch Wi-Fi
or Wi-Fi Settings on the screen.
2. The Wi-Fi settings will display the Wi-Fi hotspot name (SSID), password, and on
some vehicles, the connection type (no
Internet connection, 3G, 4G, 4G LTE), and
signal quality (poor, good, excellent).
3. To change the SSID or password, press
Qor call 1-888-4ONSTAR to connect
with an Advisor. On some vehicles, the
SSID and password can be changed in
the Wi-Fi Hotspot menu.
After initial set-up, your vehicle’s Wi-Fi
hotspot will connect automatically to your
mobile devices. Manage data usage by
turning Wi-Fi on or off on your mobile
device, by using the myChevrolet mobile app, or by contacting an OnStar Advisor. On
some vehicles, Wi-Fi can also be managed
from the Wi-Fi Hotspot menu.
MyChevrolet Mobile App (If Available)
Download the myChevrolet mobile app to
compatible Apple and Android smartphones.
Chevrolet users can access the following
services from a smartphone:
.Remotely start/stop the vehicle,
if factory-equipped.
.Lock/unlock doors, if equipped with
automatic locks.
.Activate the horn and lamps.
.Check the vehicle’s fuel level, oil life,
or tire pressure, if factory-equipped with
the Tire Pressure Monitor System.
.Send destinations to the vehicle.
.Locate the vehicle on a map (U.S.
market only).
.Turn the vehicle's Wi-Fi hotspot on/off,
manage settings, and monitor data
consumption, if equipped.
.Locate a dealer and schedule service.
.Request roadside assistance.
.Set a parking reminder with pin drop,
take a photo, make a note, and set a
timer.

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Index 351
IndexA
About Driving the Vehicle . . . . . . . . . . . . . . . . . .2
Accessories and Modifications . . . . . . . . . . . 245
Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . 199
Adaptive Cruise Control . . . . . . . . . . . . . . . . . . . 211
Add-On Electrical Equipment . . . . . . . . . . . . . .241
Additional InformationOnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 344
Additional Maintenance and Care . . . . . . . . 322
Adjustments Lumbar, Front Seats . . . . . . . . . . . . . . . . . . . . .39
Agreements Trademarks and License . . . . . . . . . . . . . . . . 165
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . 253
Air Conditioning . . . . . . . . . . . . . . . . . . . . . 174, 176
Air Filter
Life System . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253
Air Filter, Passenger Compartment . . . . . . . 179
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .178
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
How Does an Airbag Restrain? . . . . . . . . . . .54
Passenger Sensing System . . . . . . . . . . . . . . .56
What Makes an Airbag Inflate? . . . . . . . . . .54
What Will You See after an AirbagInflates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
When Should an Airbag Inflate? . . . . . . . . . 53
Where Are the Airbags? . . . . . . . . . . . . . . . . . 52 Airbags
Adding Equipment to the Vehicle . . . . . . . 60
Passenger Status Indicator . . . . . . . . . . . . . . .95
Readiness Light . . . . . . . . . . . . . . . . . . . . . . . . . .95
Servicing Airbag-Equipped Vehicles . . . . . . .59
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Alarm
Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . .29
Alert Lane Change . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
Side Blind Zone (SBZA) . . . . . . . . . . . . . . . . . . 227
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 280
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . 203, 263 Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Antenna Multi-band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Antilock Brake System (ABS) . . . . . . . . . . . . . 204 Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 311
Apple CarPlay and Android Auto . . . . . . . . . 156
Armrest Rear Seat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Assistance Program, Roadside . . . . . . . . . . . . 335
Assistance Systems for Driving . . . . . . . . . . 222