2017 TOYOTA MIRAI Ion

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Tires
Check if the treadwear indicators are showing on the tires. Also check
the tires for uneven wear, such as excessive wear on one side of the
tread.
Check the spare tire condition and pressure if not rotated.
New tread
Worn tread
Treadwear indicator
The location of treadwear indicators is shown by a “TWI” or “ Δ” mark,
etc., molded into the sidewall of each tire.
Replace the tires if the treadwear indicators are showing on a tire.
Rotate the tires in the order
shown.
To equalize tire wear and extend
tire life, Toyota recommends that
tire rotation is carried out at the
same interval as tire inspection.
Replace or rotate tires in accordance with maintenance sched-
ules and treadwear.
Checking tires
Tire rotation
Front

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Maintenance and care
Your vehicle is equipped with a tire pressure warning system that uses
tire pressure warning valves and tr ansmitters to detect low tire infla-
tion pressure before serious problems arise.
If the tire pressure drops below a predetermined level, the driver is
warned by a warning light. ( →P. 371)
◆Installing tire pressure warning valves and transmitters
When replacing tires or wheels, tire pressure warning valves and
transmitters must also be installed.
When new tire pressure warning valves and transmitters are
installed, new ID codes must be registered in the tire pressure
warning computer and the tire pr essure warning system must be
initialized. Have tire pressure warning valves and transmitter ID
codes registered by your Toyota dealer. ( →P. 333)
◆Registering ID codes
The tire pressure warning valve and transmitter is equipped with a
unique ID code. When replacing a tire pressure warning valve and
transmitter, it is necessary to register the ID code. Have the ID code
registered by your Toyota dealer.
Tire pressure warning system

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■When to replace your vehicle’s tires
Tires should be replaced if:
●The treadwear indicators are showing on a tire.
●You have tire damage such as cuts, splits, cracks deep enough to
expose the fabric, and bulges indicating internal damage
●A tire goes flat repeatedly or cannot be properly repaired due to the size
or location of a cut or other damage
If you are not sure, consult with your Toyota dealer.
■Replacing tires and wheels
If the ID code of the tire pressure warning valve and transmitter is not reg-
istered, the tire pressure warning system will not work properly. After driv-
ing for about 20 minutes, the tire pressure warning light blinks for 1
minute and stays on to indicate a system malfunction.
■Tire life
Any tire over 6 years old must be checked by a qualified technician even
if it has seldom or never been used or damage is not obvious.
■Routine tire inflation pressure checks
The tire pressure warning system does not replace routine tire inflation
pressure checks. Make su re to check tire inflation pressure as part of
your routine of daily vehicle checks.
■Maximum load of tire
Check that the maximum load of the re placement tire is greater than 1/2
of the Gross Axle Weight Ratings (GAWR) of either the front axle or the
rear axle, whichever is greater.
For the GAWR, see the Certification
Label. For the maximum load of the tire,
see the load limit at maximum cold tire
inflation pressure mentioned on the
sidewall of the tire. ( →P. 422)

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Maintenance and care
■Tire types
●Summer tires
Summer tires are high-speed performance tires best suited to highway
driving under dry conditions. Since summer tires do not have the same
traction performance as snow tires, summer tires are inadequate for
driving on snow-covered or icy ro ads. For driving on snow-covered
roads or icy roads, the use of snow tires is recommended. When install-
ing snow tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide better traction in snow and to
be adequate for driving in most winter conditions as well as for use
year-round. All season tires, however, do not have adequate traction
performance compared with snow tires in heavy or loose snow. Also, all
season tires fall short in acceleration and handling performance com-
pared with summer tires in highway driving.
●Snow tires
For driving on snow-covered roads or icy roads, we recommend using
snow tires. If you need snow tires, select tires of the same size, con-
struction and load capacity as the or iginally installed tires. Since your
vehicle has radial tires as original equipment, make sure your snow
tires also have radial construction. Do not install studded tires without
first checking local regulations fo r possible restrictions. Snow tires
should be installed on all wheels. ( →P. 253)
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tire s as snow tires is lost.

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Situations in which the tire pressure warning system may not oper-
ate properly
●In the following cases, the tire pr
essure warning system may not operate
properly.
• If non-genuine Toyota wheels are used.
• A tire has been replaced with a tire that is not an OE (Original Equip- ment) tire.
• A tire has been replaced with a tire that is not of the specified size.
• Tire chains, etc., are equipped.
• An auxiliary-supported run- flat tire is equipped.
• If a window tint that affects the radio wave signals is installed.
• If there is a lot of snow or ice on the vehicle, particularly around the wheels or wheel housings.
• If the tire inflation pressure is extremely higher than the specified level.
• If wheels without the tire pressure warning valves and transmitters
are used.
• If the ID code on the tire pressure warning valves and transmitters is not registered in the tire pressure warning computer.
●Performance may be affected in the following situations.
• Near a TV tower, electric power plant, gas station, radio station, largedisplay, airport or other facility that generates strong radio waves or
electrical noise
• When carrying a portable radio, cellular phone, cordless phone or other wireless communication device
●When the vehicle is parked, the time taken for the warning to start or go
off could be extended.
●When tire inflation pressure declines rapidly for example when a tire has
burst, the warning may not function.

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Maintenance and care
■Certification for the tire pressure warning system
FCC ID: PAXPMVC010
NOTE:
This device complies with part 15 of the FCC Rules. Operation is subject
to the following two conditions: (1) This device may not cause harmful
interference, and (2) this device must accept any interference received,
including interference that may cause undesired operation.
FCC WARNING:
Changes or modifications not expressl y approved by the party responsi-
ble for compliance could void the user ’s authority to operate the equip-
ment.
WARNING
■When inspecting or replacing tires
Observe the following precautions to prevent accidents.
Failure to do so may cause damage to parts of the drivetrain as well as
dangerous handling characteristics, which may lead to an accident
resulting in death or serious injury.
●Do not mix tires of different makes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other than those recommended by Toyota.
●Do not mix differently constructed tires (radial, bias-belted or bias-ply
tires).
●Do not mix summer, all season and snow tires.
●Do not use tires that have been used on another vehicle.
Do not use tires if you do not know how they were used previously.

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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.

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Maintenance and care
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 seems difficult to perform, contact
your Toyota dealer.
Before jacking up the vehicle
Location of the tools and jack
Wheel nut wrench
Towing eyelet Jack handle
Jack