battery TOYOTA MIRAI 2019 (in English) Service Manual

3577-1. Maintenance and care
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Maintenance and care
■Caring for leather areas
Toyota recommends cleaning the interior of the vehicle at least twice a year to
maintain the quality of the vehicle’s interior.
■ Shampooing the carpets
There are several commercial foaming-type cleaners available. U se a sponge
or brush to apply the foam. Rub in overlapping circles. Do not use water.
Wipe dirty surfaces and let them dry. Excellent results are obt ained by keep-
ing the carpet as dry as possible.
■ Seat belts
Clean with mild soap and lukewarm water using a cloth or sponge . Also
check the belts periodically for excessive wear, fraying or cut s.
■ When cleaning the carpeted portio ns of the glove box, console box, etc.
If a strong adhesive tape is used, there is a possibility that the surface of the
carpet could be damaged.
WARNING
■ Water in the vehicle
● Do not splash or spill liquid in the vehicle, such as on the fl oor, in the trac-
tion battery air intake vent, and in the trunk.
Doing so may cause the traction battery, electrical components, etc., to
malfunction or catch fire.
● Do not get any of the SRS components or wiring in the vehicle i nterior wet.
( P. 38)
An electrical malfunction may cause the airbags to deploy or no t function
properly, resulting in death or serious injury.
● Do not let the wireless charger ( P. 334) get wet. Failure to do so may
cause the charger to become hot and cause burns or could cause electric
shock resulting in death or serious injury.
■ Cleaning the interior (esp ecially instrument panel)
Do not use a polish wax or polish cleaner. The instrument panel may reflect
off the windshield, obstructing the driver’s view and leading t o an accident,
resulting in death or serious injury.

3607-2. Maintenance
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■Repair and replacement
It is recommended that genuine Toyota parts be used for repairs to ensure
performance of each system. If non-Toyota parts are used in rep lacement or if
a repair shop other than a Toyota dealer performs repairs, conf irm the war-
ranty coverage.
■ Allow inspection and repairs to be performed by a Toyota dealer
●Toyota technicians are well-trained specialists and are kept up to date with
the latest service information. They are well informed about th e operations
of all systems on your vehicle.
● Keep a copy of the repair order. It proves that the maintenance that has
been performed is under warranty coverage. If any problem should arise
while your vehicle is under warranty, your Toyota dealer will p romptly take
care of it.
WARNING
■ If your vehicle is no t properly maintained
Improper maintenance could result in serious damage to the vehi cle and
possible death or serious injury.
■ Handling of the 12-volt battery
● Fluids contained in vehicles as well as waste produced by compo nent
wear contain or emit chemicals known to the State of California to cause
cancer and birth defects or other reproductive harm. Avoid expo sure and
wash any affected area immediately.
● 12-volt battery posts, terminals and related accessories contain lead and
lead compounds which are known to cause brain damage. Wash your
hands after handling. ( P. 374)

3617-2. Maintenance
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Maintenance and care
General maintenance
Listed below are the general maintenance items that should be
performed at the intervals specified in the “Owner’s Warranty
Information Booklet” or “Own er’s Manual Supplement/Sched-
uled Maintenance Guide”. It is recommended that any problem
you notice should be brought to the attention of your Toyota
dealer or qualified s ervice shop for advice.
Motor compartment
ItemsCheck points
Brake fluidIs the brake fluid at the correct
level? ( P. 372)
CoolantIs the coolant at the correct level?
(P. 370)
Radiator/condenser
The radiator and condenser should
be free from foreign objects.
(P. 371)
Washer fluidIs there sufficient washer fluid?
(P. 373)
Tr u nk
ItemsCheck points
12-volt battery Check the connections. (P. 374)

3647-3. Do-it-yourself maintenance
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Do-it-yourself ser vice precautions
If you perform maintenance by yourself, be sure to follow the
correct procedure as given in these sections.
ItemsParts and tools
12-volt battery
condition
(  P. 3 7 4 )•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
( P. 3 7 2 )
• FMVSS No.116 DOT 3 or SAE J1703 brake fluid, or
FMVSS No.116 DOT 4 or SAE J1704 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Inverter coolant
level ( P. 370)
• “Toyota Super Long Life Coolant” or a similar high
quality ethylene glycol-based non-silicate, non-
amine, non-nitrite and non-borate coolant with long-
life hybrid organic acid technology.
For the U.S.A.:
“Toyota Super Long Life Coolant” is pre-mixed with
50% coolant and 50% deionized water.
For Canada:
“Toyota Super Long Life Coolant” is pre-mixed with
55% coolant and 45% deionized water.
• Funnel (used only for adding coolant)
Fuses ( P. 402)• Fuse with same amperage rating as original
Light bulbs
( P. 4 0 5 )
Radiator and con-
denser (
P. 371)
Tire inflation
pressure
( P. 393)• Tire pressure gauge
• Compressed air source
Washer fluid
( P. 3 7 3 )• Water or washer fluid containing antifreeze (for win-
ter use)
• Funnel (used only for adding water or washer fluid)

3657-3. Do-it-yourself maintenance
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Maintenance and care
WARNING
The motor compartment contains many mechanisms and fluids that may
move suddenly, become hot, or become electrically energized. To avoid death
or serious injury, observe the following precautions.
■ When working on the motor compartment
● Be careful not to touch the high-voltage parts or hydrogen-rela ted parts.
● Make sure that the “READY” indicator is off.
● Keep hands, clothing and tools away from the moving fans.
● Be careful not to touch the motor, inverter, radiator, etc., ri ght after driving
as they may be hot. Coolant and other fluids may also be hot.
● Do not leave anything that may burn easily, such as paper and r ags, in the
motor compartment.
● Do not smoke, cause sparks or expose an open flame to the 12-volt bat-
tery. 12-volt battery fumes are flammable.
● Be extremely cautious when working on the 12-volt battery. It c ontains poi-
sonous and corrosive sulfuric acid.
● Never touch, disassemble, remove or replace the high-voltage parts,
cables and their connectors. It can cause severe burns or electric shock
that may result in death or serious injury.
■ When working near the electric cooling fans or radiator grille
Be sure the power switch is off.
With the power switch in ON mode, the electric cooling fans may automati-
cally start to run if the air conditioning is on and/or the coolant temperature
is high. ( P. 371)
■ Safety glasses
Wear safety glasses to prevent flying or falling material, fluid spray, etc.,
from getting in your eyes.
NOTICE
■If you remove the air cleaner filter
Driving with the air cleaner filter removed may cause excessive motor wear
due to dirt in the air.

3747-3. Do-it-yourself maintenance
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12-volt batter y
The 12-volt battery is located in
the right-hand side of the trunk.
Remove the 12-volt battery cover.
Make sure that the 12-volt battery terminals are not corroded a nd that
there are no loose connections, cracks, or loose clamps.
Terminals
Hold-down clamp
Location
Removing the 12-volt battery cover
Exterior

3757-3. Do-it-yourself maintenance
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Maintenance and care
Install the 12-volt battery cover.
■Before recharging
When recharging, the 12-volt battery produces hydrogen gas which is flam-
mable and explosive. Therefore, observe the following precautio ns before
recharging:
● If recharging with the 12-volt battery installed on the vehicle , be sure to dis-
connect the ground cable.
● Make sure the power switch on the charger is off when connectin g and dis-
connecting the charger cables to the 12-volt battery.
■ After recharging/reconnecting the 12-volt battery
●Unlocking the doors using the smart key system may not be possi ble imme-
diately after reconnecting the 12-volt battery. If this happens, use the wire-
less remote control or the mechanical key to lock/unlock the do ors.
● Start the fuel cell system with the power switch in ACCESSORY m ode. The
fuel cell system may not start with the power switch turned off. However, the
fuel cell system will operate normally from the second attempt.
● The power switch mode is recorded by the vehicle. If the 12-vol t battery is
reconnected, the vehicle will return the power switch mode to t he status it
was in before the 12-volt battery was disconnected. Make sure t o turn off
the power before disconnect the 12-volt battery. Take extra car e when con-
necting the 12-volt battery if the power switch mode prior to d ischarge is
unknown.
● When the 12-volt battery is reconnected, start the fuel cell sy stem, depress
the brake pedal, and confirm that it is possible to shift into each shift posi-
tion.
If the system will not start even after multiple attempts at al l methods above,
contact your Toyota dealer.
Installing the 12-volt battery cover

3767-3. Do-it-yourself maintenance
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WARNING
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric a cid and may
produce hydrogen gas which is flammable and explosive. To reduce the risk
of death or serious injury, take the following precautions while working on or
near the 12-volt battery:
● Do not cause sparks by touching the 12-volt battery terminals w ith tools.
● Do not smoke or light a match near the 12-volt battery.
● Avoid contact with eyes, skin and clothes.
● Never inhale or swallow electrolyte.
● Wear protective safety glasses when working near the 12-volt ba ttery.
● Keep children away from the 12-volt battery.
■ Where to safely charge the 12-volt battery
Always charge the 12-volt battery in an open area. Do not charg e the
12-volt battery in a garage or closed room where there is insufficient ventila-
tion.
■ How to recharge the 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery m ay explode if
charged at a quicker rate.
■ Emergency measures regarding electrolyte
● If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and ge t immedi-
ate medical attention. If possible, continue to apply water wit h a sponge or
cloth while traveling to the nearest medical facility.
● If electrolyte gets on your skin
Wash the affected area thoroughly. If you feel pain or burning, get medical
attention immediately.
● If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the cloth-
ing and follow the procedure above if necessary.
● If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention
immediately.
■ When replacing the 12-volt battery
Use a 12-volt battery designed for this vehicle. Failure to do so may cause
gas (hydrogen) to enter the passenger compartment, causing a fire or
explosion.
For replacement of the 12-volt battery, contact your Toyota dea ler.

3777-3. Do-it-yourself maintenance
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Maintenance and care
NOTICE
■When recharging th e 12-volt battery
Never recharge the 12-volt battery while the fuel cell system i s operating.
Also, be sure all accessories are turned off.

4007-3. Do-it-yourself maintenance
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Electronic key batter y
●Flathead screwdriver
● Small flathead screwdriver
● Lithium battery CR2032
Take out the mechanical key.
( P. 129)
Remove the cover.
To prevent damage to the key,
cover the tip of the flathead screw-
driver with a rag.
Remove the depleted battery.
Insert a new battery with the “+”
terminal facing up.
Replace the battery with a n ew one if it is depleted.
You will need the following items:
Replacing the battery
1
2
3