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6177-3. Do-it-yourself maintenance
7
Maintenance and care
■Situations in which the tire pressure warning system may not oper-
ate properly
●In the following cases, the tire pressure warning system may no t operate
properly.
• If non-genuine Toyota wheels are used.
• When a replacement tire is used, the system may not operate cor-
rectly due to the structure of the replacement tire.
• A tire has been replac ed with a tire that is not of the specif ied size.
• Tire chains etc . are equipped.
• An auxiliary-supported ru n-flat tire is equipped.
• If a window tint that affects the radio wave signals is instal led.
• 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 sp ecified
level.
• If wheel without the tire pressure warning valve and transmitt er is
used.
• If the ID code on the tire pressure warning valves and transmi tters 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 stat ion, large
display, airport or other facilit y 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 s tart or go
off could be extended.
●When tire inflation pressure declines rapidly for example when a tire has
burst, the warning may not function.
■The initialization operation
●Make sure to carry out initializ ation after adjusting the tire inflation pres-
sure.
Also, make sure the tires are co ld before carrying out initialization or tire
inflation pressure adjustment.
●If you have accidentally turned the power switch off during ini tialization,
it is not necessary to press the reset swit ch again as initialization will
restart automatically when the power switch has been turned to ON
mode for the next time.
●If you accidentally press the reset switch when initialization is not neces-
sary, adjust the tire inflation pressure to the specified level when the
tires are cold, and cond uct initialization again.
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7-3. Do-it-yourself maintenance
■When initialization of the tire pressure warning system has fai led
Initialization can be completed in a few minutes. However, in the following
cases, the settings have not been record ed and the system will not oper-
ate properly. If repeated attempts to record tire inflation pre ssure settings
are unsuccessful, have the vehicle inspected by your Toyota dealer.
●When operating the initializatio n of the system, the tire pressure warning
light does not flash 3 times an d the setting message does not a ppear on
the multi-information display.
●After driving for a certain period of time since the initializa tion has been
completed, the warning light comes on after blinking for 1 minute.
WARNING
■When inspecting or replacing tires
Observe the following precaut ions to prevent accidents.
Failure to do so may cause damage to parts of the drive train as well as
dangerous handling characteristics, which may lead to an accide nt
resulting in death o r serious injury.
●Do not mix tires of different ma kes, models or tread patterns.
Also, do not mix tires of remarkably different treadwear.
●Do not use tire sizes other th an those recommended by Toyota.
●Do not mix differently constructed tires (radial, bias-belted o r 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 kn ow how they were used previously.
■When initializing the tire pressure warning system
Do not initialize the tire press ure warning system without firs t adjusting
the tire inflation pressure to t he specified level. Otherwise, the tire pres-
sure warning light may not come on even if the tire inflation p ressure is
low, or it may come on when the tire inflation pressure is actu ally nor-
mal.
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PRIUS PRIME_OM_OM47E74U_(U)
6197-3. Do-it-yourself maintenance
7
Maintenance and care
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 val ve caps. If the tire valve caps are not
installed, water could enter the tire pressure warning valves a nd the
tire pressure warning valves could be bound.
●When replacing tire valve caps, do not use tire valve caps othe r than
those specified. The cap may become stuck.
■To avoid damage to the tire pressure warning valves and transmi t-
ters
When a tire is repaired with liquid sealants, the tire pressure warning valve and transmitter may not operate properly. If a liquid sea lant 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 repairing or replac ing the
tire. ( P. 613)
■Driving on rough roads
Take particular care when drivi ng on roads with loose surfaces or pot-
holes.
These conditions may cause losses in tire inflation pressure, reducing
the cushioning ability of the t ires. In addition, driving on ro ugh roads
may cause damage to the tires themselves, as well as the vehicl e’s
wheels and body.
■If tire inflation pressure of each tire becomes low while drivi ng
Do not continue driving, or your t ires and/or wheels may be ruined.
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7-3. Do-it-yourself maintenance
Tire inflation pressure
The recommended cold tire infla-
tion pressure and tire size are dis-
played on the tire and loading
information label. (P. 733)
Tire inflation pressure
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PRIUS PRIME_OM_OM47E74U_(U)
6217-3. Do-it-yourself maintenance
7
Maintenance and care
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 drive train
If a tire needs frequent inflating , have it checked by your Toyota dealer.
Inspection and adjustment procedure
1
2
1
2
3
4
5
6
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7-3. Do-it-yourself maintenance
■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 after 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 resulting in death or serious i njury:
●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 tire damage while driving (due to road h azards,
expansion joints, sharp edges 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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7-3. Do-it-yourself maintenance
7
Maintenance and care
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.
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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7-3. Do-it-yourself maintenance
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning
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. 613)
WARNING
■When replacing wheels
●Do not use wheels that are a different size from those recommen ded in
the Owner’s Manual, as this may result in a loss of handling control.
●Never use an inner tube in a leaking wheel which is designed fo r a
tubeless tire. Doing so may result in an accident, causing deat h or seri-
ous injury.
■When installing the wheel nuts
Never use oil or grease on the wheel bolts or wheel nuts.
Oil and grease may cause the wheel nuts to be excessively tight ened,
leading to bolt or disc wheel damage. In addition, the oil or grease can
cause the wheel nuts to loosen and the wheel may fall off, causing an
accident and resulting in death or serious injury. Remove any o il or
grease from the wheel bolts or wheel nuts.
■Use of defective wheels prohibited
Do not use cracked or deformed wheels.
Doing so could cause the tire to leak air during driving, possibly causing
an accident.