ECU MAZDA MODEL 3 HATCHBACK 2020 (in English) Service Manual

SignalWarning Refer to
Door-Ajar Warning Light 7-36
*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 t he 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 Light
2-72
Security Indicator Light
3-41
(Green)KEY Indicator Light 4-5
Wrench Indication/Indicator Light*14-28
*Shift Position Indication
4-36
Lights-On Indicator Light
4-44
Headlight High-Beam Indicator LightHeadlight
High-Low Beam 4-47
Flashing the Headlights 4-47
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 CONTEN T 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 TH ROUGH 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 CH ANGES 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 OU T 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 EFFO RT 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 HERE BY 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 MERCHANTABIL ITY, SATISFACTORY
QUALITY, FITNESS FOR A PARTICULAR PURP OSE, ACCURACY, QUIET ENJOYMENT, AND
NONINFRINGEMENT OF THIRD PARTY RIGHTS.
AS EXAMPLES, AND WITHOUT LIMITATI ON, 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 CONTEN T 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 OU T 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 di straction 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 Maz
da 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, resear ch, and product development.
Using the QR codes or URLs below, refer to the Connected Servic e 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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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 off 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 indefinitely 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
WA R N I N G
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 hood opening, slide the latch lever to the
left, and lift up the hood.


Maintenance and Care
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3. Grasp the support rod in the paddedarea 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 onthe support rod, and secure the support
rod in the clip. Ve rify 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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NOTE
Changing the coolant should be done by
an Authorized Mazda Dealer.
Inspect the antifreeze protection and
coolant level in the coolant reservoir at
least once a year―at the beginning of the
winter season―and before traveling where
temperatures may drop below freezing.

Inspect the condition and connections of
all cooling system and heater hoses.
Replace any that are swollen or
deteriorated.

The coolant should be at full in the
radiator and between the FULL and LOW
marks on the coolant reservoir when the
engine is cool.

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 off 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 reserv oir is empty or new
coolant is required frequently, consult an
Authorized Mazda Dealer.
Maintenance and Care
Owner Maintenance
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▼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 off 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 a
battery replacement purchase.
Key Battery Replacement
▼ Key Battery Replacement
If the buttons on the transmitter are
inoperable and the operation indicator
light does not flash, the battery may be
dead.
Replace with a new battery before the
transmitter becomes unusable.
CAUTION

Make sure the battery is installed
correctly. Battery leakage could occur if it
is not installed correctly.
 When replacing the battery, be careful
not to touch any of the internal circuitry
and electrical terminals, bend the
electrical terminals, or get dirt in the
transmitter as the transmitter could be
damaged.
 There is the danger of explosion if the
battery is not correctly replaced.
 Dispose of used batteries according to
the following instructions.
 Insulate the plus and minus terminals
of the battery using cellophane or
equivalent tape.
 Never disassemble.
 Never throw the battery into fire or
water.
 Never deform or crush.
 Replace only with the same type battery
(CR2032 or equivalent).
Maintenance and Care
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Fuses
▼Fuses
Your vehicle's electrical system is
protected by fuses.

If any lights, accessories, or controls do
not work, inspect the appropriate circuit
protector. If a fuse has blown, the inside
element will be melted.

If the same fuse blows
again, avoid using
that system and consult an Authorized
Mazda Dealer as soon as possible.
▼ Fuse Replacement
Replacing the fuses on the vehicle's left
side
If the electrical system does not work, first
inspect the fuses on the vehicle's left side.

1. Make sure the ignition is switched off,
and other switches are off.
2. Open the fuse panel cover.
3. Pull the fuse straight out with the fuse 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.
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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

WA R N I N G
Do not replace the main fuse by
yourself. Have an Authorized Mazda
Dealer perform the replacement:
Replacing the fuse by yourself is
dangerous because the MAIN fuse is a
high current fuse. Incorrect
replacement could cause an electrical
shock or a short circuit resulting in a
fire.
4. Reinstall the cover and make sure that it is securely installed.
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