3187-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
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)
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.
3387-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
NOTICE
■Repairing or replacing tires, wheels, tire pressure warning valves,
transmitters and tire valve caps
●When removing or fitting the wheels, tires or the tire pressure warning
valves and transmitters, contact your Toyota dealer as the tire pres-
sure warning valves and transmitters may be damaged if not handled
correctly.
●Make sure to install the tire valve caps. If the tire valve caps are not
installed, water could enter the tire pressure warning valves and the
tire pressure warning valves could be bound.
●When replacing tire valve caps, do not use tire valve caps other than
those specified. The cap may become stuck.
■To avoid damage to the tire pressure warning valves and transmit-
ters
When a tire is repaired with liquid sealants, the tire pressure warning
valve and transmitter may not operate properly. If a liquid sealant is
used, contact your Toyota dealer or other qualified service shop as soon
as possible. After use of liquid sealant, make sure to replace the tire
pressure warning valve and transmitter when replacing the tire.
( → P. 333)
■Driving on rough roads
Take particular care when driving on roads with loose surfaces or pot-
holes.
These conditions may cause losses in tire inflation pressure, reducing
the cushioning ability of the tires. In addition, driving on rough roads
may cause damage to the tires themselves, as well as the vehicle’s
wheels and body.
■If tire inflation pressure of e ach tire becomes low while driving
Do not continue driving, or your tires and/or wheels may be ruined.
3487-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U■
Instructions for checking tire inflation pressure
When checking tire inflation pressure, observe the following:
●Check only when the tires are cold.
If your vehicle has been parked for at least 3 hours or has not been
driven for more than 1 mile or 1.5 km, you will get an accurate cold tire
inflation pressure reading.
●Always use a tire pressure gauge.
It is difficult to judge if a tire is
properly inflated based only on its appear-
ance.
● It is normal for the tire inflation pressure to be higher after driving as
heat is generated in the tire. Do no t reduce tire inflation pressure after
driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle is
balanced.
WARNING
■Proper inflation is critical to save tire performance
Keep your tires properly inflated.
If the tires are not properly inflated, the following conditions may occur
which could lead to an accident resulting in death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overheated tires
●Air leaking from between tire and wheel
●Wheel deformation and/or tire damage
●Greater possibility of ti re damage while driving (due to road hazards,
expansion joints, sharp edges in the road, etc.)
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to put the tire valve caps back on.
If a valve cap is not installed, dirt or moisture may get into the valve and
cause an air leak, resulting in decreased tire inflation pressure.
3517-3. Do-it-yourself maintenance
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7
Maintenance and care
Air conditioning filter
Turn the power switch off.
Open the glove box. Slide off
the damper.
Push the surface on the left
side of the glove box inward,
undo the upper left claw, then
push the surface on the right
side of the glove box inward
and undo the upper right claw.
Lower the glove box from the
completely open position, undo
the lower claws, and then
remove the glove box.
The air conditioning filter must be changed regularly to maintain
air conditioning efficiency.
Removal method
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3
4
3527-3. Do-it-yourself maintenance
MIRAI_OM_USA_OM62023U
Remove the filter cover.
Remove the air conditioning fil-
ter and replace it with a new
one.
The “↑UP” marks shown on the fil-
ter should be pointing up.
■ Checking interval
Inspect and replace the air conditioning filter according to the maintenance
schedule. In dusty areas or areas with heavy traffic flow, early replacement
may be required. (For scheduled maintenance information, please refer to the
“Schedule Maintenance Guide” or “Owner’s Manual Supplement”.)
■ If air flow from the vents decreases dramatically
The filter may be clogged. Check the filter and replace if necessary.
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6
NOTICE
■When using the air conditioning system
Make sure that a filter is always installed.
Using the air conditioning system without a filter may cause damage to the
system.
3738-2. Steps to take in an emergency
MIRAI_OM_USA_OM62023U
8
When trouble arises
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact
sensors, side impact sensors (front door), side impact sensors (front), side
impact sensors (rear), driver’s seat posit ion sensor, driver’s seat belt buckle
switch, front passenger occupant classification system (ECU and sensors),
“AIR BAG ON” indicator light, “AIR BAG OFF” indicator light, front passen-
ger’s seat belt buckle switch, seat belt pretensioners, airbags, interconnect-
ing wiring and power sources. ( →P. 38)
■ Front passenger detection sensor, seat belt reminder and warning
buzzer
● If luggage is placed on the front passenger seat, the front passenger de\
tec-
tion sensor may cause the warning light to flash and the warning buzzer to
sound even if a passenger is not sitting in the seat.
● If a cushion is placed on the seat, the sensor may not detect a passenger,
and the warning light may not operate properly.
■ Electric power steering system warning light (warning buzzer)
When the 12-volt battery charge becomes insufficient or the voltage tempo-
rarily drops, the electric power steer ing system warning light may come on
and the warning buzzer may sound.
■
When the tire pressure warning light comes on
Inspect the appearance of the tire to check that the tire is not punctured.
If the tire is punctured: → P. 381
If the tire is not punctured:
After turning the power switch to off, turn it to ON mode again and make
sure the tire pressure warning light comes on or blinks.
The tire pressure warning light comes on
After the temperature of the tires have lowered sufficiently, check the
tire inflation pressure and adjust it to the specified level.
If the warning light does not go out even after several minutes, check
that the tire inflation pressu re is at the specified level.
If the warning light does not go out even after several minutes, have the
vehicle inspected by your Toyota dealer immediately.
The tire pressure warning light is blinking for 1 minute, and then comes
on
Malfunction in the tire pressure warning system. Have the system
checked by your Toyota dealer immediately.
■The tire pressure warning light may come on due to natural causes
The tire pressure warning light may come on due to natural causes such
as natural air leaks and tire inflat ion pressure changes caused by tem-
perature. In this case, adjusting the ti re inflation pressure will turn off the
warning light (afte r a few minutes).
■Conditions that the tire pressure warning system may not function
properly
→ P. 3 3 6
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3778-2. Steps to take in an emergency
MIRAI_OM_USA_OM62023U
8
When trouble arises
*: A buzzer sounds the first time a message is shown on the multi-informa-tion display.
■ System warning lights
The master warning light does not come on or flash in the following cases.
Instead, a separate system warning light will come on along with a message
shown on the multi-information display.
●Malfunction of the ABS
The ABS warning light comes on. ( →P. 370)
● Malfunction of the charging system
The charging system warning light comes on. ( →P. 369)
■ If “High FC Temperature Re duced Power” is displayed
Lower the speed while check the safety, and run the vehicle like this for
several minutes.
If the message goes off, the vehicle can be driven as is, since it temporarily
overheated.
This message may be displayed when driving under severe operating con-
ditions.
(For example, when driving up a long steep hill.)
■ If “Maintenance Required for Hybr id Battery Cooling Parts at Your
Dealer” is displayed
The filter may be clogged, or the air intake vent or duct may be blocked. Have
the vehicle inspected by your Toyota dealer.
■ If “Shift to P Before Exiting Vehicle” is displayed
Message is displayed when the driver’s door is opened without turning the
power switch to off with the shift position in any position other than P.
Shift the shift position to P.
■ If “Shift is in N Release Accelerat or Before Shifting” is displayed
Message is displayed when the accelerator pedal has been depressed and
the shift position is in N. Release the accelerator pedal and shift the shift posi-
tion to D or R.
Comes on⎯Does not sound
Indicates a condition, such as mal-
function of electrical components,
their condition, or indicates the
need for maintenance
Flashes⎯Does not sound
Indicates a situation, such as
when an operation has been per-
formed incorrectly, or indicates
how to perform an operation cor-
rectly
System
warning
light
Warning buzzer*Warning
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