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491
4-3. Do-it-yourself maintenance
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4
Maintenance and care
■Tire inflation pressure check interval
You should check tire inflation pressure every two weeks, or at least
once a month.
■Effects of incorrect tire inflation pressure
Driving with incorrect ti
re inflation pressure ma y result in the following:
●Reduced fuel efficiency
●Reduced driving comfort and tire life
●Reduced safety
●Damage to the drive train
If a tire needs frequent inflating, have it checked by your Toyota dealer.
■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.
The appearance of the tire can be mi sleading. In addition, tire infla-
tion pressure that is even just a few pounds off can affect ride quality
and handling.
●Do not reduce tire inflation pressure after driving. It is normal for tire
inflation pressure to be higher after driving.
●Never exceed the vehicle capacity weight.
Passengers and luggage weight should be placed so that the vehicle
is balanced.
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492 4-3. Do-it-yourself maintenance
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CAUTION
■Proper inflation is critical to save tire performance
Keep your tires properly inflated. Otherwise, the following conditions
may occur and result in an accident causing death or serious injury:
●Excessive wear
●Uneven wear
●Poor handling
●Possibility of blowouts resu lting from overheated tires
●Poor sealing of the tire bead
●Wheel deformation and/or tire separation
●A greater possibility of tire damage from road hazards
NOTICE
■When inspecting and adjusting tire inflation pressure
Be sure to put the tire valve caps back on.
Without the valve caps, dirt or mo isture could get into the valve and
cause air leakage, which could result in an accident. If the caps are lost,
replace them as soon as possible.
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494 4-3. Do-it-yourself maintenance
PRIUS PHV_OM_OM47856U_(U)
■When replacing wheels
The wheels of your vehicle are equipped with tire pressure warning
valves and transmitters that allow the tire pressure warning system to
provide advance warning in the event of a loss in tire inflation pressure.
Whenever wheels are replaced, tire pressure warning valves and trans-
mitters must be installed. (P. 480)
CAUTION
■When replacing wheels
●Do not use wheels that are a different size from those recommended in
the Owner’s Manual, as this may resu lt in a loss of handling control.
●Never use an inner tube in a leaking wheel which is designed for a
tubeless tire. Doing so may result in an accident, causing death 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 tightened,
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 oil or
grease from the wheel bolts or wheel nuts.
●Be sure to install the wheel nuts with
the tapered ends facing inward.
Installing the nuts with the tapered
ends facing outward can cause the
wheel to break and eventually cause
the wheel to come off while driving,
which could lead to an accident
resulting in death or serious injury.
Tapered
portion
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540 5-2. Steps to take in an emergency
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Warning lightWarning light/DetailsCorrection procedure
Tire pressure warning
light
When the light comes
on:
Low tire inflation pres-
sure such as
• Natural causes ( P. 542)
• Flat tire ( P. 451) Adjust the tire
inflation pressure
to the specified
level.
The light will turn
off after a few
minutes. In case
the light does
not turn off even
if the tire infla-
tion pressure is
adjusted, have
the system
checked by your
Toyota dealer.
When the light comes
on after blinking for 1
minute:
Malfunction in the tire
pressure warning sys-
tem
( P. 544) Have the system
checked by your
Toyota dealer.
Master warning light
The warning light comes
on and flashes to indicate
that the master warning
system has detected a
malfunction.
P. 5 4 8
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542 5-2. Steps to take in an emergency
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■Electric power steering system wa rning light (warning buzzer)
When the 12-volt battery charge becomes insufficient or the voltage tempo-
rarily drops, the electric power steering system warning light may come on
and the warning buzzer may sound.
■ If the malfunction indicator lamp comes on while driving
First check the following:
● Is the fuel tank cap loose?
If it is, tighten it securely.
The malfunction indicator lamp will go off after several driving trips.
If the malfunction indicator lamp does not go off even after several trips, con-
tact your Toyota dealer as soon as possible.
■
When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level.
Pushing the tire pressure warning reset switch will not turn off the tire
pressure warning light.
■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 tire inflation pressure will turn off the
warning light (after a few minutes).
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When trouble arises
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5-2. Steps to take in an emergency
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■If the tire pressure warning system is not functioning
The tire pressure warning system will be disabled in the following condi-
tions:
(When the condition be
comes normal, the system will work properly.)
●If tires not equipped with tire pressure warning valves and transmit-
ters are used
●If the ID code on the tire pressure warning valves and transmitters is
not registered in the tire pressure warning computer
●If the tire inflation pressure is 73 psi (500 kPa, 5.1 kgf/cm2 or bar) or
higher
The tire pressure warning system may be disabled in the following condi-
tions:
(When the condition be comes normal, the system will work properly.)
●If electronic devices or facilities using similar radio wave frequencies
are nearby
●If a radio set at a similar frequency is in use in the vehicle
●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 non-genuine Toyota wheels are used (Even if you use Toyota
wheels, the tire pressure warning system may not work properly with
some types of tires.)
●If tire chains are used
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5
When trouble arises
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5-2. Steps to take in an emergency
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CAUTION
■If the tire pressure warning light comes on
Be sure to observe the following precautions. Failure to do so could
cause a loss of vehicle control and result in death or serious injury.
●Stop your vehicle in a safe place as
soon as possible. Adjust the tire
inflation pressure immediately.
●If the tire pressure warning light comes on even after tire inflation pres-
sure adjustment, it is pr obable that you have a flat tire. Check the tires.
If a tire is flat, repair the flat ti re by using emergency tire puncture
repair kit.
●Avoid abrupt maneuvering and braking. If the vehicle tires deteriorate,
you could lose control of the steering wheel or the brakes.
■If a blowout or sudden air leakage should occur
The tire pressure warning syste m may not activate immediately.
■Maintenance of the tires
Each tire, including the spare (if provided), should be checked monthly
when cold and inflated to the inflation pressure recommended by the
vehicle manufacturer on the vehicle placard or tire inflation pressure
label (tire and load information label). (If your vehicle has tires of a differ-
ent size than the size indicated on the vehicle placard or tire inflation
pressure label [tire and load information label], you should determine the
proper tire inflation pr essure for those tires.)
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546 5-2. Steps to take in an emergency
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CAUTION
As an added safety feature, your vehicle has been equipped with a tire
pressure monitoring system (TPMS-ti re pressure warning system) that
illuminates a low tire pressure telltal e (tire pressure warning light) when
one or more of your tires is significantly under-inflated. Accordingly,
when the low tire pressu re telltale (tire pressure warning light) illumi-
nates, you should stop and check your tires as soon as possible, and
inflate them to the proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel effi ciency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
Please note that the TPMS (tire pressure warning system) is not a sub-
stitute for proper tire main tenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-inflation has not reached the
level to trigger illu mination of the TPMS low tire pressure telltale (tire
pressure warning light).
Your vehicle has also been equipped with a TPMS (tire pressure warning
system) malfunction indicator to indi cate when the system is not operat-
ing properly. The TPMS (tire pressure warning system) malfunction indi-
cator is combined with the low tire pressure telltale (tire pressure
warning light). When the system det ects a malfunction, the telltale will
flash for approximately one minute an d then remain continuously illumi-
nated. This sequence will continue upon subsequent vehicle start-ups as
long as the malfunction exists. When the malfunction indi cator is illumi-
nated, the system may not be able to detect or signal low tire pressure
as intended.