ECU MAZDA MODEL 3 HATCHBACK 2021 Service Manual

SignalWarning Refer to
*Liftgate-Ajar Warning Indication 7-37
Door-Ajar Warning Light
7-37
*1 The light turns on when the ignition is switched on for an operation check, and turns off a few
seconds later or when the engine is started. If the light does not turn on or remains turned on, have
the vehicle inspected at an Authorized Mazda Dealer.
▼ Indication/Indicator Lights
These lights turn on or
flash to notify the user of the system operation status or a
system malfunction.
Signal Indicator Refer to
(Green)Seat Belt Indicator Light (Rear seat)
2-27
*Front Passenger Air Bag Deactivation Indicator Light2-71
Security Indicator LightImmobilizer
System3-41
Theft-Deterrent System
3-42
Malfunction 7-34
(Green) KEY Indicator Light
4-5
Wrench Indication/Indicator Light*14-29
*Shift Position Indication4-38
Lights-On Indicator Light
4-46
When Driving
Instrument Cluster and Display
*Some models.4-25
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AS EXAMPLES, AND WITHOUT LIMITATION, MAZDA DISCLAIMS ANY
WARRANTY REGARDING THE ACCURACY OF DATA PROVIDED BY THE
APPLICATION, SUCH AS THE ACCURACY OF DIRECTIONS, ESTIMATED TRAVEL
TIME, SPEED LIMITS, ROAD CONDITIONS, NEWS, WEATHER, TRAFFIC, OR
OTHER CONTENT PROVIDED BY APPLE, ITS AFFILIATES, OR THIRD PARTY
PROVIDERS; MAZDA DOES NOT GUARANTEE AGAINST LOSS OF APPLICATION
DATA, WHICH MAY BE LOST AT ANY TIME; MAZDA DOES NOT GUARANTEE
THAT THE APPLICATION OR ANY SERVICES PROVIDED THROUGH THEM WILL
BE PROVIDED AT ALL TIMES OR THAT ANY OR ALL SERVICES WILL BE AVAILABLE
AT ANY PARTICULAR TIME OR LOCATION. FOR EXAMPLE, SERVICES MAY BE
SUSPENDED OR INTERRUPTED WITHOUT NOTICE FOR REPAIR, MAINTENANCE,
SECURITY FIXES, UPDATES, ETC., SERVICES MAY BE UNAVAILABLE IN YOUR AREA
OR LOCATION, ETC.
IN ADDITION, YOU UNDERSTAND THAT CHANGES IN THIRD PARTY
TECHNOLOGY OR GOVERNMENT REGULATION MAY RENDER THE SERVICES
AND/OR APPLICATIONS OBSOLETE AND/OR UNUSABLE. TO THE EXTENT NOT
PROHIBITED BY LAW, IN NO EVENT SHALL MAZDA OR ITS AFFILIATES BE LIABLE
FOR PERSONAL INJURY, OR ANY INCIDENTAL, SPECIAL, INDIRECT OR
CONSEQUENTIAL DAMAGES WHATSOEVER, INCLUDING, WITHOUT
LIMITATION, DAMAGES FOR LOSS OF PROFITS, CORRUPTION OR LOSS OF
DATA, FAILURE TO TRANSMIT OR RECEIVE ANY DATA, BUSINESS INTERRUPTION
OR ANY OTHER COMMERCIAL DAMAGES OR LOSSES, ARISING OUT OF OR
RELATED TO THE APPLICATION OR YOUR USE OF OR INABILITY TO USE THE
APPLICATION OR INFORMATION ON THE APPLICATION.
 When using Apple CarPlay™, please avoid distraction and use Apple CarPlay™
responsibly.
Stay fully aware of driving conditions and always obey applicable laws.
NOTE
Apple CarPlay™ is provided by Apple® and its use is subject to your agreement to
the Apple CarPlay™ terms of use, which are included as part of the Apple iOS
terms of use.
When using Apple CarPlay™, location, speed, and other vehicle data is transferred
to your iPhone®. For further details, refer to Apple®’s Privacy Policy.
Interior Features
Mazda Connect
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Android Auto™
CAUTION
YOU EXPRESSLY ACKNOWLEDGE AND AGREE THAT USE OF ANDROID AUTO™
(“THE APPLICATION”) IS AT YOUR SOLE RISK AND THAT THE ENTIRE RISK AS TO
SATISFACTORY QUALITY, PERFORMANCE, ACCURACY AND EFFORT IS WITH
YOU TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, AND THAT
THE APPLICATION AND INFORMATION ON THE APPLICATION IS PROVIDED “AS
IS” AND “AS AVAILABLE,” WITH ALL FAULTS AND WITHOUT WARRANTY OF ANY
KIND, AND MAZDA HEREBY DISCLAIMS ALL WARRANTIES AND CONDITIONS
WITH RESPECT TO THE APPLICATION AND INFORMATION ON THE
APPLICATION, EITHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES AND/OR CONDITIONS OF
MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A PARTICULAR
PURPOSE, ACCURACY, QUIET ENJOYMENT, AND NONINFRINGEMENT OF
THIRD PARTY RIGHTS.
AS EXAMPLES, AND WITHOUT LIMITATION, MAZDA DISCLAIMS ANY
WARRANTY REGARDING THE ACCURACY OF DATA PROVIDED BY THE
APPLICATION, SUCH AS THE ACCURACY OF DIRECTIONS, ESTIMATED TRAVEL
TIME, SPEED LIMITS, ROAD CONDITIONS, NEWS, WEATHER, TRAFFIC, OR
OTHER CONTENT PROVIDED BY GOOGLE, ITS AFFILIATES, OR THIRD PARTY
PROVIDERS; MAZDA DOES NOT GUARANTEE AGAINST LOSS OF APPLICATION
DATA, WHICH MAY BE LOST AT ANY TIME; MAZDA DOES NOT GUARANTEE
THAT THE APPLICATION OR ANY SERVICES PROVIDED THROUGH THEM WILL
BE PROVIDED AT ALL TIMES OR THAT ANY OR ALL SERVICES WILL BE AVAILABLE
AT ANY PARTICULAR TIME OR LOCATION. FOR EXAMPLE, SERVICES MAY BE
SUSPENDED OR INTERRUPTED WITHOUT NOTICE FOR REPAIR, MAINTENANCE,
SECURITY FIXES, UPDATES, ETC., SERVICES MAY BE UNAVAILABLE IN YOUR AREA
OR LOCATION, ETC.
IN ADDITION, YOU UNDERSTAND THAT CHANGES IN THIRD PARTY
TECHNOLOGY OR GOVERNMENT REGULATION MAY RENDER THE SERVICES
AND/OR APPLICATIONS OBSOLETE AND/OR UNUSABLE. TO THE EXTENT NOT
PROHIBITED BY LAW, IN NO EVENT SHALL MAZDA OR ITS AFFILIATES BE LIABLE
FOR PERSONAL INJURY, OR ANY INCIDENTAL, SPECIAL, INDIRECT OR
CONSEQUENTIAL DAMAGES WHATSOEVER, INCLUDING, WITHOUT
LIMITATION, DAMAGES FOR LOSS OF PROFITS, CORRUPTION OR LOSS OF
DATA, FAILURE TO TRANSMIT OR RECEIVE ANY DATA, BUSINESS INTERRUPTION
OR ANY OTHER COMMERCIAL DAMAGES OR LOSSES, ARISING OUT OF OR
RELATED TO THE APPLICATION OR YOUR USE OF OR INABILITY TO USE THE
APPLICATION OR INFORMATION ON THE APPLICATION.
 When using Android Auto™, please avoid distraction and use Android Auto™
responsibly.
Stay fully aware of driving conditions and always obey applicable laws.
Interior Features
Mazda Connect
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Connected Service (U.S.A only)
▼Connected Service Overview
There are several types of connected services available via Mazda Connect. Some
services may require you to download the MyMazda app to your smartphone and
subscribe to the services, while others may require you to pair your smartphone to
the vehicle via Bluetooth
®. In addition, on a regular basis and unless you opt-out,
your vehicle will automatically transmit certain geo-location, driving behavior data,
and vehicle health information to Mazda for product quality, data analysis, research,
and product development. Using the QR codes or URLs below, refer to the
Connected Service Owner's Manual and Privacy Policy for more details and opt-out
options.
Connected Service Owner's Manual
https://www.mazdausa.com/static/manuals/mazda-connected-service/
index.html
Privacy
Mazda maintains a Privacy Statement which describes how we collect, use, share,
store and secure data from your vehicle equipped with connected services.
We provide you with connected services by collecting and using your personal
information and vehicle location, health and driving data.
To learn more about our Privacy Statement, please visit: https://
www.mazdausa.com/site/privacy-connectedservices
Interior Features
Mazda Connect
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Rear Coat Hooks
▼Rear Coat Hooks
WARNING
Never hang heavy or sharp objects on
the assist grips and coat hooks:
Hanging heavy or sharp-ended objects
such as a coat hanger from the assist
grips or coat hooks is dangerous as
they can
fly o ff and hit an occupant in
the cabin if a curtain air bag was to
deploy, which could result in serious
injury or death.
Always hang clothes on the coat hooks
and the assist grips without hangers.
Storage Compartments
▼ Storage Compartments
WARNING
Keep storage boxes closed when
driving:
Driving with the storage boxes open is
dangerous. To reduce the possibility of
injury in an accident or a sudden stop,
keep the storage boxes closed when
driving.
When loading cargo, make sure that it
is completely secured:
If the cargo is not completely secured,
it may move or collapse while driving
or during sudden braking , resulting in
injury or an accident.
Do not put articles in storage spaces
with no lid:
Putting articles in storage spaces with
no lid is dangerous as they could be
thrown around the cabin during
sudden braking , maneuvering, or
acceleration and cause an accident
depending on how the article is stored.
CAUTION
Do not leave lighters or eyeglasses in
the storage boxes while parked under
the sun. A lighter could explode or the
plastic material in eyeglasses could
deform and crack from high
temperature.
Interior Features
Interior Equipment
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If you must run the engine while
working under the hood, make
certain that you remove all jewelry
(especially rings, bracelets, watches,
and necklaces) and all neckties,
scarves, and similar loose clothing
before getting near the engine or
cooling fan which may turn on
unexpectedly:
Working under the hood with the
engine running is dangerous. It
becomes even more dangerous when
you wear jewelry, loose clothing or
have long hair or a long beard.
Either can become entangled in
moving parts and result in injury.
Pull over to a safe location, then
switch the ignition o ff and make sure
the fan is not running before
attempting to work near the cooling
fan:
Working near the cooling fan when it is
running is dangerous. The fan could
continue running inde finitely even if
the engine has stopped and the engine
compartment temperature is high. You
could be hit by the fan and seriously
injured.
Do not leave items in the engine
compartment:
After you have finished checking or
doing servicing in the engine
compartment, do not forget and leave
items such as tools or rags in the
engine compartment.
Tools or other items left in the engine
compartment could cause engine
damage or a fire leading to an
unexpected accident.
Hood
▼ Hood
WARNING
Always check that the hood is closed
and securely locked:
A hood that is not closed and securely
locked is dangerous as it could
fly open
while the vehicle is moving and block
the driver's vision which could result in
a serious accident.
▼ Opening the Hood
1. With the vehicle parked, pull the
release handle to unlock the hood.

2. Insert your hand into the hoodopening , slide the latch lever in the
direction of the allow as shown in
the illustration, and lift up the
hood.


Maintenance and Care
Owner Maintenance
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3. Grasp the support rod in thepadded area and secure it in the
support rod hole indicated by the
arrow to hold the hood open.

1. Pad
2. Support rod
▼Closing the Hood
1. Check under the hood area to
make certain all filler caps are in
place and all loose items (e.g.
tools, oil containers, etc.) have
been removed.
2. Lift the hood, grasp the padded area on the support rod, and secure
the support rod in the clip. Verify
that the support rod is secured in
the clip before closing the hood.

1. Clip

3. Lower the hood slowly to a height of about 20 cm (7.9 in) above its
closed position and then let it drop.
CAUTION
When closing the hood, do not push it
excessively such as by applying your
weight. Otherwise, the hood could be
deformed.
Maintenance and Care
Owner Maintenance
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SKYACTIV-G 2.5T

FULL
LOW
If it is at or near LOW, add enough
coolant to the coolant reservoir to
provide freezing and corrosion
protection and to bring the level to
FULL.
Securely tighten the coolant reservoir
tank cap after adding coolant.
CAUTION
 Radiator coolant will damage paint.
Rinse it o ff quickly if spilled.
 If the “FL22” mark is shown on or
near the cooling system cap, use of
FL-22 is recommended when
replacing engine coolant. Using
engine coolant other than FL -22 may
cause serious damage to the engine
and cooling system.

If the coolant reservoir is empty or new
coolant is required frequently, consult
an Authorized Mazda Dealer.
Brake/Clutch Fluid
▼ Inspecting Brake/Clutch Fluid
Level
WARNING
If the brake/clutch
fluid level is low,
have the brakes inspected:
A low brake/clutch fluid level is
dangerous.
A low level could indicate brake lining
wear or a brake system leak which
could cause the brakes to fail and lead
to an accident.
The brakes and clutch draw fluid from
the same reservoir.
Inspect the fluid level in the reservoir
regularly. It should be kept between
the MAX and MIN lines.
The level normally drops with
accumulated distance, a condition
associated with wear of brake and
clutch linings. If it is excessively low,
have the brake/clutch system
inspected by an Authorized Mazda
Dealer.
Maintenance and Care
Owner Maintenance
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Keep all flames and sparks
away from open battery cells because
hydrogen gas is produced from open
battery cells while charging the
battery or adding battery fluid:
Flames and sparks near open battery
cells are dangerou s. Hydrogen gas,
produced during normal battery
operation, could ignite and cause the
battery to explode. An exploding
battery can cause serious burns and
injuries. Keep all flames including
cigarettes and sparks away from open
battery cells.
NOTE
Before performing battery
maintenance, remove the battery
cover.

▼ Battery Maintenance
To get the best service from a battery:
Keep it securely mounted.Keep the top clean and dry.Keep terminals and connections
clean, tight, and coated with
petroleum jelly or terminal grease.
Rinse o
ff spilled electrolyte
immediately with a solution of water
and baking soda.
If the vehicle will not be used for an
extended time, disconnect the
battery cables and charge the battery
every 6 weeks.
▼ Battery Replacement
Contact an Authorized Mazda Dealer
for battery replacement.
Maintenance and Care
Owner Maintenance
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3. Pull the fuse straight out with thefuse puller provided on the fuse
block located in the engine
compartment.
4. Inspect the fuse and replace it if it is
blown.
1. Normal
2. Blown

5. Insert a new fuse of the same
amperage rating , and make sure it
fits tightly. If it does not
fit tightly,
have an expert install it. Consult an
Authorized Mazda Dealer.
If you have no spare fuses, borrow
one of the same rating from a
circuit not essential to vehicle
operation, such as the audio or
accessory socket circuit.
CAUTION
Always replace a fuse with a
genuine Mazda fuse or equivalent
of the same rating. Otherwise, you
may damage the electric system.
6. Reinstall the cover and make sure that it is securely installed.
Replacing the fuses under the hood
If the headlights or other electrical
components do not work and the fuses
in the cabin are normal, inspect the
fuse block under the hood.
If a fuse is blown, it must be replaced.
Follow these steps:

1. Make sure the ignition is switched
off, and other switches are
off.
2. Remove the fuse block cover.
3. If any fuse but the MAIN fuse is blown, replace it with a new one of
the same amperage rating .
1. Normal
2. Blown

Maintenance and Care
Owner Maintenance
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