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3867-3. Do-it-yourself maintenance
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Replacing the tire
●Stop the vehicle on a hard, flat surface.
● Set the parking brake.
● Shift the shift position to P.
● Stop the fuel cell system.
When raising your vehicle with a jack, position the jack cor-
rectly. Improper placement may damage your vehicle or cause
injury.
If necessary tire replacement seem s difficult to perform, contact
your Toyota dealer.
Before jacking up the vehicle
Location of the tools and jack
Wheel nut wrench
To w i n g e y e l e t Jack handle
Jack
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3937-3. Do-it-yourself maintenance
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Maintenance and care
Tire inflation pressure
The recommended cold tire infla-
tion pressure and tire size are dis-
played on the tire and loading
information label. (P. 471)
Tire inflation pressure
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3947-3. Do-it-yourself maintenance
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Tire valve
Tire pressure gauge
Remove the tire valve cap.
Press the tip of the tire pressure gauge onto the tire valve.
Read the pressure using the gauge gradations.
If the tire inflation pressure is not at the recommended level, adjust
the pressure.
If you add too much air, press the center of the valve to defla te.
After completing the tire inflation pressure measurement and
adjustment, apply soapy water to the valve and check for leakage.
Put the tire valve cap back on.
■Tire inflation pressure check interval
You should check tire inflation p ressure every two weeks, or at least once
a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pressure
Driving with incorrec t tire inflation pressure may result in th e following:
●Reduced fuel economy
●Reduced driving comfort and poor handling
●Reduced tire life due to wear
●Reduced safety
●Damage to the drivetrain
If a tire needs frequent inflating , have it checked by your Toyota dealer.
Inspection and adjustment procedure
1
2
3
4
5
6
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7
Maintenance and care
■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 o nly on its appear-
ance.
● It is normal for the tire inflation pressure to be higher afte r driving as
heat is generated in the tire. Do not reduce tire inflation pre ssure after
driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehi cle is
balanced.
WARNING
■Proper inflation is critical to save tire performance
Keep your tires properly inflated.
If the tires are not properly in flated, the following conditions may occur
which could lead to an accident r esulting in death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resulting from overh eated tires
●Air leaking from between tire and wheel
●Wheel deformation and/or tire damage
●Greater possibility of tire damage while driving (due to road hazards,
expansion joints, sharp ed ges in the road, etc.)
NOTICE
■When inspecting and adjusti ng 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 pressu re.
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Wheels
When replacing wheels, care should be taken to ensure that they are
equivalent to those removed in load capacity, diameter, rim wid th and
inset
*.
Replacement wheels are available at your Toyota dealer.
*: Conventionally referred to as “offset”.
Toyota does not recommend using the following:
● Wheels of different sizes or types
● Used wheels
● Bent wheels that hav e been straightened
● Use only Toyota wheel nuts and wrenches designed for use with
your aluminum wheels.
● When rotating, repairing or changi ng your tires, check that the
wheel nuts are still tight afte r driving 1000 miles (1600 km).
● Be careful not to damage the aluminum wheels when using tire
chains.
● Use only Toyota genuine balance we ights or equivalent and a plas-
tic or rubber hammer when balancing your wheels.
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warn ing
valves and transmitters that allow the tire pressure warning sy stem to
provide advance warning in the event of a loss in tire inflatio n pressure.
Whenever wheels are replaced, tir e pressure warning valves and trans-
mitters must be installed. ( P. 379)
If a wheel is bent, cracked or heavily corroded, it should be
replaced. Otherwise, the tire may separate from the wheel or
cause a loss of handling control.
Wheel selection
Aluminum wheel precautions
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407
8When trouble arises
MIRAI_OM_USA_OM62073U8-1. Essential information
Emergency flashers .......... 408
If your vehicle has to be stopped in an
emergency ...................... 409
If the vehicle is trapped in rising water.................. 410
8-2. Steps to take in an emergency
If your vehicle needs to be towed ......................... 411
If you think something is wrong .............................. 417
If a warning light turns on or a warning buzzer
sounds ............................ 418
If a warning message is displayed......................... 426
If you have a flat tire.......... 432
If the fuel cell system will not start ........................... 447
If the electronic key does not operate properly ........ 449
If the 12-volt battery is discharged ...................... 452
If your vehicle overheats ... 457
If the vehicle becomes stuck ............................... 463
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4178-2. Steps to take in an emergency
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8
When trouble arises
If you think something is wrong
●Fluid leaks un der the vehicle.
(Water dripping from the air conditioning a fter use is normal.)
● Flat-looking tires or uneven tire wear
● The high coolant temperature war ning light flashes or comes on
● Excessive tire squeal when cornering
● Strange noises related to the suspension system
● Pinging or other noises rel ated to the fuel cell system
● Stumbling or running roughly
● Appreciable loss of power
● Vehicle pulls heavily to one side when braking
● Vehicle pulls heavily to one s ide when driving on a level road
● Loss of brake effectiveness, spongy feeling, pedal almost touch es
the floor
If you notice any of the followi ng symptoms, your vehicle proba -
bly needs adjustment or repair. Contact your Toyota dealer as
soon as possible.
Visible symptoms
Audible symptoms
Operational symptoms
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4218-2. Steps to take in an emergency
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8
When trouble arises
*1: Brake warning buzzer: When there is a malfunction that leads to a decline in the brak e effective-
ness, a buzzer sounds while at the same time a warning light co mes on.
*2: Parking brake engaged warning buzzer:
P. 200
*3: Open door warning buzzer:
A buzzer will sound if the vehicle reaches a speed of 3 mph (5 km/h) or
more with any door open.
Driver’s and front passenger’ s seat belt reminder light
(warning buzzer)
*4
Warns the driver and/or front passenger to fasten their
seat belts
Fasten the seat belt.
If the front passenger’s seat is occupied, the front
passenger’s seat belt also needs to be fastened to
make the warning light (warning buzzer) turn off.
Master warning light
A buzzer sounds and the warning light comes on and
flashes to indicate that the master warning system has
detected a malfunction.
P. 426
Tire pressure warning light
Indicates low tire pressure due to one of the following:
• Flat tire
• Natural causes
• The tire pressure warning system is malfunctioning
Immediately stop the veh icle in a safe place.
Handling method ( P. 4 2 3 )
Brake Override System/Drive-St art Control/Parking Sup-
port Brake function (for st atic objects) (if equipped)
*5
Indicates that:
• The Brake Override System is operating;
• The Brake Override System is malfunctioning (with
warning buzzer);
• The Drive-Start Control is operating (with warning buzzer);
• The Drive-Start Control is malfunctioning (with warning buzzer); or
• The Parking Support Brake function (for static objects)
(if equipped) is operating (with warning buzzer)
(P. 279)
Follow the instruction that are displayed on the multi-
information display.
Warning lightWarning light/Details/Actions