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7-3. Do-it-yourself maintenance
■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 regis-
tered, the tire pressure warning system will not work properly. After driving 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 pres-
sure checks. Make sure 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 replacement 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 side-
wall of the tire. ( P. 548)
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7-3. Do-it-yourself maintenance
■Situations in which the tire pressu re warning system may not operate
properly
● In the following cases, the tire pressure warning system may not operate
properly.
• If non-genuine Toyota wheels are used.
• When a replacement tire is used, the system may not operate correctly
due to the structure of the replacement 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 ex tremely higher than the specified level.
• If wheel without the tire pressure warning valve and transmitter is 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, large dis-
play, airport or other facility that generates strong radio waves or electri-
cal 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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4377-3. Do-it-yourself maintenance
7
Maintenance and care
■The initialization operation
●Make sure to carry out initialization after adjusting the tire inflation pressure.
Also, make sure the tires are cold before carrying out initialization or tire
inflation pressure adjustment.
● If you have accidentally turned the power switch off during initialization, it is
not necessary to press the reset switch 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 necessary,
adjust the tire inflation pressure to the specified level when the tires are
cold, and conduct initialization again.
■ When initialization of the tire pressure warning system has failed
Initialization can be completed in a few minutes. However, in the following
cases, the settings have not been recorded and the system will not operate
properly. If repeated attempts to record tire inflation pressure settings are
unsuccessful, have the vehicle inspected by your Toyota dealer.
● When operating the tire pressure warning reset switch, the tire pressure
warning light does not blink 3 times.
● After carrying out the initialization procedure, the tire pressure warning light
blinks for 1 minute then stays on after driving for 20 minutes.
■ Certification for the tire pressure warning system
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WARNING
■When inspecting or replacing tires
Observe the following precautions 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 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 ti res (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.
■ When initializing the tire pressure warning system
Do not operate the tire pressure warning reset switch without first adjusting
the tire inflation pressure to the spec ified level. Otherwise, the tire pressure
warning light may not come on even if the tire inflation pressure is low, or it
may come on when the tire inflation pressure is actually normal.
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4397-3. 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 pressure
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 transmitters
When a tire is repaired with liquid seal ants, 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.
Make sure to replace the tire pressure warning valve and transmitter when
replacing the tire. ( P. 432)
■ Driving on rough roads
Take particular care when driving on roads with loose surfaces or potholes.
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 each tire becomes low while driving
Do not continue driving, or your tires 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. 543)
Tire inflation pressure
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4417-3. 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 deflate.
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 pressure every two weeks, or at least once
a month.
Do not forget to check the spare.
■Effects of incorrect tire inflation pressure
Driving with incorrect tire inflation pressure may result in the 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 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 not 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 tire 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.