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2636-1. Using the air conditioning system and defogger
6
Interior features
MIRAI_OM_USA_OM62023U■
Fogging up of the windows
●The windows will easily fog up when the humidity in the vehicle is high.
Turning on will dehumidify the air from the outlets and defog the wind-
shield effectively.
● If you turn off, the windows may fog up more easily.
● The windows may fog up if the recirculated air mode is used.
■ Windshield fog detection function
When automatic mode is set, the humidity sensor ( →P. 266) detects fog on
the windshield and controls the air conditioning system to prevent fog.
■ Outside/recirculated air mode
●When driving on dusty roads such as tunnels or in heavy traffic, set the out-
side/recirculated air mode button to recirculated air mode. This is effective in
preventing outside air from entering the vehicle interior. During cooling oper-
ation, setting the recirculated air mode will also cool the vehicle interior
effectively.
● Outside/recirculated air mode may automatically switch depending on the
temperature setting or the inside temperature.
■ Operation of the air conditioni ng system in ECO HEAT/COOL mode
● In ECO HEAT/COOL mode, the air conditioning system is controlled as fol-
lows to prioritize fuel efficiency:
• Fluid (heating) heater and compressor operation controlled to restrict
heating/cooling capacity
• Fan speed restricted when automatic mode is selected
● To improve air conditioning performance, perform the following operations:
• Adjust the temperature settings and fan speed
• Touch while in , and is set
• Touch while in , and ECO HEAT/COOL mode is canceled
■ Operation of the air conditio ning system in Eco drive mode
When ECO MODE switch is pressed, oper ations switch over to ECO HEAT/
COOL mode. ( →P. 183)
■ When the outside temperature exceeds 75°F (24°C) and the air condition-
ing system is on
● In order to reduce the air conditioning power consumption, the air condition-
ing system may switch to recirculated air mode automatically. This may also
reduce fuel consumption.
● Recirculated air mode is selected as a default mode when the power switch
is turned to ON mode.
● It is possible to switch to outside air mode at any time by pressing .
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3147-2. 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 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)
Page 315 of 464
3157-2. Maintenance
MIRAI_OM_USA_OM62023U
7
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 “Owner’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 service shop for advice.
Motor compartment
ItemsCheck points
Brake fluidIs the brake fluid at the correct
level? ( →P. 326)
CoolantIs the coolant at the correct level?
(→P. 324)
Radiator/condenser
The radiator and condenser should
be free from foreign objects.
(→P. 325)
Washer fluidIs there sufficient washer fluid?
(→P. 327)
Tr u nk
ItemsCheck points
12-volt battery Check the connections. (→P. 328)
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3177-2. Maintenance
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7
Maintenance and care
Seat belts
• Do the seat belts operatesmoothly?
• The seat belts should not be dam-
aged.
Seats• Do the seat controls operate prop-erly?
Steering wheel
• Does the steering wheel rotatesmoothly?
• Does the steering wheel have the correct amount of free play?
• There should not be any strange sounds coming from the steering
wheel.
Vehicle exterior
ItemsCheck points
ItemsCheck points
Doors/trunk• Do the doors/trunk operatesmoothly?
Hood• Does the hood lock system workproperly?
Fluid leaks
• There should not be any signs of
fluid leakage after the vehicle has
been parked.
Tires
• Is the tire inflation pressure cor-rect?
• The tires should not be dam- aged or excessively worn.
• Have the tires been rotated
according to the maintenance
schedule?
• The wheel nuts should not be
loose.
Windshield wipers
• The wiper blades should not show
any signs of cracking, splitting,
wear, contamination or deforma-
tion.
• The wiper blades should clear the windshield without streaking or
skipping.
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3187-3. Do-it-yourself maintenance
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Do-it-yourself service 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. 328)•Grease
• Conventional wrench (for terminal clamp bolts)
Brake fluid level
(→ P. 326)• FMVSS No.116 DOT 3 or SAE J1703 brake fluid
• Rag or paper towel
• Funnel (used only for adding brake fluid)
Inverter coolant
level ( →P. 324)
• “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.
“Toyota Super Long Life Coolant” is pre-mixed with
50% coolant and 50% deionized water.
• Funnel (used only for adding coolant)
Fuses ( →P. 355)• Fuse with same amperage rating as original
Light bulbs
(→ P. 358)⎯
Radiator and con-
denser (
→P. 325)⎯
Tire inflation
pressure
(→ P. 346)• Tire pressure gauge
• Compressed air source
Washer fluid
(→ P. 327)• Water or washer fluid containing antifreeze (for win-
ter use)
• Funnel (used only for adding water or washer fluid)
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3197-3. Do-it-yourself maintenance
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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 323 of 464
3237-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
7
Maintenance and care
Motor compartment
Washer fluid tank (→P. 327)
Brake fluid reservoir (→ P. 326)
Inverter coolant reservoir (→ P. 324)
Fuse boxes ( →P. 355)
Fuel cell stack coolant radiator (→ P. 325) Inverter coolant radiator
(→ P. 325)
Condenser ( →P. 325)
Electric cooling fans
Fuel cell stack coolant reser-
voir ( →P. 324)
Fuel cell stack coolant sub
radiator ( →P. 325)
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3267-3. Do-it-yourself maintenance
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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.