2012 TOYOTA SIENNA maintenance

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4-3. Do-it-yourself maintenance
4
Maintenance and care
SIENNA_U (OM45477U)
■Initializing the tire pressure warning system
Initialize the system with the tire infl
ation pressure adjusted to the speci-
fied level.
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tires as snow tires is lost.
■If you press the tire pressure warning reset switch accidentally
If initialization is performed, adjust t he tire inflation pressure to the speci-
fied level and initialize the tire pressure warning system again.
■When the initialization of the tire pressure warning system has
failed
Initialization can be completed in a few minutes. However, in the follow-
ing cases, the settings has not bee n 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 pres-
sure warning light doe s not blink 3 times.
●After driving for a certain period of time since the initialization has
been completed, the wa rning light comes on after blinking for 1
minute.

680 4-3. Do-it-yourself maintenance
SIENNA_U (OM45477U)
■Tire pressure warning system certification
FCC ID:GQ4-45T
FCC ID:GQ4-32T
FCC ID:GQ4-37R
For vehicles sold in the U.S.A.
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 expre ssly approved by the party responsi-
ble for compliance could void the user’s authority to operate the equip-
ment.
For vehicles sold in Canada
NOTE:
Operation is subject to the following two conditions: (1) this device may
not cause interference, and (2) this de vice must accept any interference,
including interference that may caus e undesired operation of the device.

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4-3. Do-it-yourself maintenance
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Maintenance and care
SIENNA_U (OM45477U)
CAUTION
■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 han-
dling characteristics, which may lead to an accident resulting in death or
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 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.
●Do not tow if your vehicle has a compact spare tire installed.
■When initializing the tire pressure warning system
Do not operate the tire pressure wa rning reset switch without first adjust-
ing the tire inflation pr essure to the specified 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 ti re inflation pressure is actually nor-
mal.

682 4-3. Do-it-yourself maintenance
SIENNA_U (OM45477U)
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.
●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. Make sure to replace the tire pressure warning valve and
transmitter when replacing the tire. ( P. 674)
■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 each tire becomes low while driving
Do not continue driving, or your tires and/or wheels may be ruined.

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4-3. Do-it-yourself maintenance
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Maintenance and care
SIENNA_U (OM45477U)
Tire inflation pressure
■Tire inflation pressure
The recommended cold tire inflation pressure and tire size are
displayed on the tire and loading information label. ( 
P. 7 9 4)

684 4-3. Do-it-yourself maintenance
SIENNA_U (OM45477U)
■Inspection and adjustment procedure
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 lev-
els, adjust the pressure.
If you add too much air, pres s 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.
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4-3. Do-it-yourself maintenance
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Maintenance and care
SIENNA_U (OM45477U)
■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 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 re filling, 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.

686 4-3. Do-it-yourself maintenance
SIENNA_U (OM45477U)
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.