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3147-2. Maintenance
MIRAI_OM_USA_OM62023U
■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 replacement or if
a repair shop other than a Toyota dealer performs repairs, confirm 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 the 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 promptly take
care of it.
WARNING
■ If your vehicle is not properly maintained
Improper maintenance could result in serious damage to the vehicle and
possible death or serious injury.
■ Handling of the 12-volt battery
● Fluids contained in vehicles as well as waste produced by component
wear contain or emit chemicals known to the State of California to cause\
cancer and birth defects or other reproductive harm. Avoid exposure 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. 328)
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3197-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
7
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-related 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., right 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 rags, 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 contains poi-
sonous and corrosive sulfuric acid.
● Take care because brake fluid can harm your hands or eyes and damage
painted surfaces. If fluid gets on your hands or in your eyes, flush the
affected area with clean water immediately.
If you still experience discomfort, consult a doctor.
● 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, t he electric cooling fans may automati-
cally start to run if the air conditioning is on and/or the coolant temperature
is high. ( →P. 325)
■ 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.
Page 320 of 464
3207-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
Hood
Pull the hood lock release lever.
The hood will pop up slightly.
Pull up the auxiliary catch lever
and lift the hood.
Release the lock from the inside of the vehicle to open the hood.
1
2
WARNING
■ Pre-driving check
Check that the hood is fully closed and locked.
If the hood is not locked properly, it may open while the vehicle is in motion
and cause an accident, which may result in death or serious injury.
Page 322 of 464
3227-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
WARNING
■When raising your vehicle
Make sure to observe the following precautions to reduce the possibility of
death or serious injury:
● Make sure to set the floor jack properly at the jack point.
Raising the vehicle with an improperly positioned floor jack will damage
the vehicle and may cause the vehicle to fall off the floor jack.
● Do not jack up on the hydrogen tanks nor the rear suspension.
Rear suspension
Hydrogen tanks
Front
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3257-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
7
Maintenance and care
■If the inverter coolant level drops within a short time of replenishing
Visually check the radiators, hoses, inverter coolant reservoir cap, drain cock
and water pump.
If you cannot find a leak, have your Toyota dealer test the cap and check for
leaks in the cooling system.
Check the radiator and condenser and clear away any foreign objects.
If either of the above parts is ex tremely dirty or you are not sure of
their condition, have your vehicle inspected by your Toyota dealer.
WARNING
■ When the fuel cell system is hot
Do not remove the coolant reservoir caps.
The cooling system may be under pressure and may spray hot coolant if the
cap is removed, causing serious injuries, such as burns.
NOTICE
■When adding coolant
Coolant is neither plain water nor stra ight antifreeze. The correct mixture of
water and antifreeze must be used to provide proper lubrication, corrosion
protection and cooling. Be sure to read the antifreeze or coolant label.
■ If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.
Radiator and condenser
WARNING
■When the fuel cell system is hot
Do not touch the radiator or condenser as they may be hot and cause seri\
-
ous injuries, such as burns.
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3267-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U■
Checking fluid level
The brake fluid level should be
between the “MAX” and “MIN”
lines on the tank.
“MAX”
“MIN”
■Adding fluid
Make sure to check the fluid type and prepare the necessary item.
■Brake fluid can absorb moisture from the air
Excess moisture in the brake fluid can cause a dangerous loss of braking effi-
ciency. Use only newly opened brake fluid.
Brake fluid
Fluid typeFMVSS No.116 DOT 3 or SAE J1703 brake fluid
ItemClean funnel
WARNING
■When filling the reservoir
Take care as brake fluid can harm your hands and eyes and damage
painted surfaces.
If fluid gets on your hands or in your eyes, flush the affected area with clean
water immediately.
If you still experience discomfort, see a doctor.
NOTICE
■If the fluid level is low or high
It is normal for the brake fluid level to go down slightly as the brake pads
wear out or when the fluid level in the accumulator is high.
If the reservoir needs frequent refilling, there may be a serious problem.
Page 327 of 464
3277-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
7
Maintenance and care
If none of the washer do not work
or the warning message appears
on the multi-information display,
the washer tank may be empty.
Add washer fluid. (→P. 376)
Washer fluid
WARNING
■When adding washer fluid
Do not add washer fluid when the fuel cell system is hot or operating, as
washer fluid contains alcohol and may catch fire if spilled on the fuel cell
system, etc.
NOTICE
■Do not use any fluid other than washer fluid
Do not use soapy water or antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces.
■ Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the label of the washer fluid bot-
tle.
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3307-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
WARNING
■Chemicals in the 12-volt battery
The 12-volt battery contains poisonous and corrosive sulfuric acid 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 with 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 battery.
● 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 charge the 12-
volt battery in a garage or closed room where there is insufficient ventila-
tion.
■ How to recharge th e 12-volt battery
Only perform a slow charge (5 A or less). The 12-volt battery may 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 get immedi-
ate medical attention. If possible, continue to apply water with 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 dealer.