ECU MAZDA MODEL CX-3 2021 Repair Manual

▼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
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).
The following conditions indicate that the
battery power is low:
The KEY indicator light (green) flashes
in the instrument cluster for about 30
seconds after the engine is switched
OFF.
Maintenance and Care
Owner Maintenance
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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 isblown.
Normal 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 OUTLET 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.
Maintenance and Care
Owner Maintenance
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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 .
Normal
Blown
WARNING
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.
Maintenance and Care
Owner Maintenance
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2. Wipe off the remaining detergent usinga cloth soaked in clean water and
wrung out well.
▼Active Driving Display
Maintenance*
The combiner and mirror surface have a
special coating. When cleaning it, do not
use a hard cloth, a cloth with a rough
surface, or cleaning detergent. Use a
fine-textured, soft cloth.
If a chemical solvent
gets on the combiner
or mirror surface, wipe it off immediately.
Otherwise, they could be damaged and the
surface coating could be scratched.
▼ Panel Maintenance
If a panel becomes soiled, wipe it off with
a soft cloth soaked in clean water and
thoroughly wrung out.
If some areas require further cleaning, use
the following procedure:
1. Wipe the soiled ar
ea with a soft cloth
soaked in a mild detergent (approx.
5 %) diluted with water.
2. Wipe off the remaining detergent using a cloth soaked in clean water and
wrung out well.
NOTE
Be particularly careful when cleaning
shiny surface panels and metallic parts
such as plating as they can be scratched
easily.
▼Cleaning the Window Interiors
If the windows become covered with an
oily, greasy, or waxy film, clean them with
glass cleaner. Follow the directions on the
container.
CAUTION

Do not scrape or scratch the inside of the
window glass. It could damage the
thermal filaments.
 When washing the inside of the window
glass, use a soft cloth dampened in
lukewarm water, gently wiping the
thermal
filaments.
Use of glass cleaning products could
damage the thermal filaments.
▼ Cleaning the Floor Mats
Rubber floor mats should be cleaned with
mild soap and water only.
WA R N I N G
Do not use rubber cleaners, such as tire
cleaner or tire shine, when cleaning rubber
floor
mats:
Cleaning the rubber floor mats with rubber
cleaning products makes the floor mats
slippery.
This may cause an accident when
depressing the accelerator, brake, or clutch
(Manual transaxle) pedal or when getting
in or out of the vehicle.
After removing the floor mats for
cleaning, always reinstall them securely
(page 3-41).
Maintenance and Care
Appearance Care
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▼Jack
To remove the jack
1.
(With luggage board)
Lift up the luggage board.
2. (With luggage board)
Pull the luggage board outward a little
and insert the opposite end into the
holders so that the luggage board
stands.
Lugg age board
Holders
3. Lift the luggage mat.
Lugg age mat
4. Remove the cargo sub compartment.
5. Remove the cover.
Tabs
6. Turn the wing bolt and jack screw
counterclockwise.
Win g bolt
Jack screw
To secure the jack
1. Insert the wing bolt into the jack with the jack screw pointing down and turn
If Trouble Arises
Flat Tire
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the wing bolt clockwise to temporarily
tighten it.
2. Turn the jack screw in the direction
shown in the figure.
Win g bolt
Jack screw
3. Turn the wing bolt completely to secure the jack.
NOTE
If the jack is not completely secured, it
could rattle while driving. Make sure
the jack screw is sufficiently tightened.
4. Insert the cover tabs and install the cover.
NOTE
Verify that the cover is securely
installed.
Maintenance
Always keep the jack clean.
Make sure the moving parts are kept
free from dirt or rust.
Make sure the screw thread is
adequately lubricated.
▼ Spare Tire
Your Mazda has a temporary spare tire.
The temporary spare tire is lighter and
smaller than a conventional tire, and is
designed only for emergency use and
should be used only for VERY short
periods. Temporary spare tires should
NEVER be used fo
r long drives or
extended periods.
WA R N I N G
Do not install the temporary spare tire on
the front wheels (driving wheels):
Driving with the temporary spare tire on
one of the front driving wheels is
dangerous. Handling will be affected. You
could lose control of the vehicle, especially
on ice or snow bound roads, and have an
accident. Move a regular tire to the front
wheel and install the temporary spare tire
to the rear.
CAUTION
 When using the temporary spare tire,
driving stability may decrease compared
to when using only the conventional tire.
Drive carefully.
 To avoid damage to the temporary spare
tire or to the vehicle, observe the
following precautions:
 Do not exceed 80 km/h (50 mph).
 Avoid driving over obstacles. Also, do
not drive through an automatic car
wash. This tire's diameter is smaller
than a conventional tire, so the ground
clearance is reduced.
 Do not use a tire chain on this tire
because it will not fit properly.
 Do not use your temporary spare tire
on any other vehicle, it has been
designed only for your Mazda.
 Use only one temporary spare tire on
your vehicle at the same time.
If Trouble Arises
Flat Tire
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hold-down bolt counterclockwise and
remove the spare tire.

Spare tire hold-down bolt
To secure the spare tire
Store the spare tire in the reverse order of
removal. After storing, verify that the
spare tire is stored securely.
Changing a Flat Tire
NOTE
If the following occurs while driving, it
could indicate a flat tire.
Steering becomes difficult.
The vehicle begins to vibrate
excessively.
The vehicle pulls in one direction.
If you have a flat tire, drive slowly to a
level spot that is well off the road and out
of the way of traffic to change the tire.
Stopping in traffic or on the shoulder of a
busy road is dangerous.
WA R N I N G
Be sure to follow the directions for
changing a tire:
Changing a tire is dangerous if not done
properly. The vehicle can slip off the jack
and seriously injure someone.
No person should plac e any portion of their
body under a vehicle that is supported by a
jack.
Never allow anyone inside a vehicle
supported by a jack:
Allowing someone to remain in a vehicle
supported by a jack is dangerous. The
occupant could cause the vehicle to fall
resulting in serious injury.
NOTE
Make sure the jack is well lubricated
before using it.
1. Park on a hard, level surface off the right-of-way and firmly set the parking
brake.
If Trouble Arises
Flat Tire
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5. Use the lug wrench to tighten the nutsin the order shown.

If you are unsure of how tight the nuts
should be, have them inspected at an
Authorized Mazda Dealer.
Nut tightening torque
N·m (kgf·m, ft·lbf) 108
―147 (12 ―14,
80 ―108)
WA R N I N G
Always securely and correctly tighten
the lug nuts:
Improperly or loosely tightened lug
nuts are dangerous. The wheel could
wobble or come off. This could result in
loss of vehicle control and cause a
serious accident.
Be sure to reinstall the same nuts you
removed or replace them with metric
nuts of the same configuration:
Because the wheel studs and lug nuts
on your Mazda have metric threads,
using a non-metric nut is dangerous.
On a metric stud, it would not secure
the wheel and would damage the stud,
which could cause the wheel to slip off
and cause an accident.
6. (Without flat tire belt)
Store the damaged tire in the luggage
compartment.
(With flat tire belt)
Remove the luggage compartment
cover (if equipped).
Refer to Luggag e Compartment on
page 3-21.

Strap

Pin
Pin
7. Remove the belt for securing the flat tire.
8. (With luggage board)
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Flat Tire
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12. Thread the buckle through the wheel asshown in the figure.

13. Thread the belt through the bucklewhile pressing the tire to the seatback.

14. Pull the belt end to secure the flat tire.
15. Insert the luggag e compartment cover
from the top of the luggage
compartment opening with the cloth
side of the cover facing outward, and
slide it between the flat tire and the
inside perimeter of the luggage
compartment opening.

16. Check the tire inflation pressure. Refer to the specification charts on
page 9-7.
17. Have the flat tire repaired or replaced as soon as possible.
WA R N I N G
Do not drive with any tires that have
incorrect air pressure:
Driving on tires with incorrect air pressure
is dangerous. Tires with incorrect pressure
could affect handling and result in an
accident. When you check the regular tires'
air pressure, check the spare tire, too.
NOTE
To prevent the jack and tool from rattling,
store them properly.
If Trouble Arises
Flat Tire
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Route the jumper cables away from parts that will be moving:
Connecting a jumper cable near or to moving parts (cooling fans, belts) is dangerous. The
cable could get caught when the engine starts and cause serious injury.
CAUTION
Use only a 12 V booster system. You can damage a 12 V starter, ignition system, and other
electrical parts beyond repair with a 24 V power supply (two 12 V batteries in series or a 24 V
motor generator set).
1. Move the booster vehicle so that its battery is as close as possible to your vehicle's battery.
2. Make sure that the power such as for the headlights and air conditioner is turned off.
3. Remove the battery cover.
4. Turn off the booster vehicle's engine and connect the jumper cables in the following
order.
Make sure that the jumper cables are securely connected so that they do not disconnect
due to engine vibrations.
1st lead
Positive (+) terminal on the discharged battery
Positive (+) terminal on booster vehicle's battery
2nd lead
Negative (-) terminal on booster vehicle's battery
If Trouble Arises
Battery Runs Out
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