
494
SIENNA_OM_OM08007U_(U)
7-3. Do-it-yourself maintenance
WARNING
■Chemicals in the battery
Batteries contain poisonous and corrosive sulfuric acid and may produce
hydrogen gas which is flammable and explosive. To reduce the risk of death
or serious injury, take the following precautions while working on or near the
battery:
●Do not cause sparks by touching the battery terminals with tools.
● Do not smoke or light a match near the battery.
● Avoid contact with eyes, skin and clothes.
● Never inhale or swallow electrolyte.
● Wear protective safety glasses when working near the battery.
● Keep children away from the battery.
■ Where to safely charge the battery
Always charge the battery in an open area. Do not charge the battery in a
garage or closed room where there is insufficient ventilation.
■ How to recharge the battery
Only perform a slow charge (5 A or less). The battery may explode if
charged at a quicker rate.
■ Emergency measures regarding electrolyte
●If electrolyte gets in your eyes
Flush your eyes with clean water for at least 15 minutes and get immedi-
ate medical attention. If possible, continue to apply water with a sponge or
cloth while traveling to the nearest medical facility.
● If electrolyte gets on your skin
Wash the affected area thoroughly. If you feel pain or burning, get medical
attention immediately.
● If electrolyte gets on your clothes
It can soak through clothing on to your skin. Immediately take off the cloth-
ing and follow the procedure above if necessary.
● If you accidentally swallow electrolyte
Drink a large quantity of water or milk. Get emergency medical attention
immediately.
NOTICE
■When recharging the battery
Never recharge the battery while the engine is running. Also, be sure all
accessories are turned off.

SIENNA_OM_OM08007U_(U)
4957-3. Do-it-yourself maintenance
7
Maintenance and care
If any washer does not work or the
warning message appears on the
multi-information display, the
washer tank may be empty. Add
washer fluid.
Washer fluid
WARNING
■When refilling washer fluid
Do not refill washer fluid when the engine is hot or running, as washer fluid
contains alcohol and may catch fire if spilled on the engine etc.
NOTICE
■Do not use any fluid other than washer fluid
Do not use soapy water or engine antifreeze instead of washer fluid.
Doing so may cause streaking on the vehicle’s painted surfaces.
■ Diluting washer fluid
Dilute washer fluid with water as necessary.
Refer to the freezing temperatures listed on the label of the washer fluid bot-
tle.

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4977-3. Do-it-yourself maintenance
7
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. ( P. 547)
Vehicles with compact spare tire : The compact spare tire is not
equipped with the tire pressure warning valve and transmitters.
◆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 valve and transmitter ID
codes registered by your Toyota dealer. ( P. 498)
◆Initializing the tire pressure warning system
When the tire size is changed, the tire pressure warning system
must be initialized.
When the tire pressure warning system is initialized, the current tire
inflation pressure is set as the benchmark pressure.
■How to initialize the tire pressure warning system
Park the vehicle in a safe place and turn the engine switch off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire inflation
pressure level. ( P. 606)
Make sure to adjust the tire pressu re to the specified cold tire infla-
tion pressure level. The tire pressure warning system will operate
based on this pressure level.
Turn the engine switch to the “ON” position (vehicles without a
smart key system) or IGNITION ON mode (vehicles with a smart
key system).
Tire pressure warning system
1
2
3

498
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7-3. Do-it-yourself maintenance
Press and hold the tire pres-
sure warning reset switch
until the tire pressure warn-
ing light blinks slowly 3 times.
Vehicles without a smart key system: Wait for a few minutes with
the engine switch in the “ON” position and then turn the engine
switch to the “ACC” or “LOCK” position.
Vehicles with a smart key system: Wait for a few minutes with the
engine switch in IGNITION ON mode and then turn the engine
switch off.
◆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.
4
5

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4997-3. Do-it-yourself maintenance
7
Maintenance and care
■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 sure to check tire inflation pressure as part of
your routine of daily vehicle checks.
■Maximum load of tire
Check that the number given by dividing the maximum load by 1.10 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
sidewall of the tire. ( P. 612)

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5017-3. Do-it-yourself maintenance
7
Maintenance and care
■Situations in which the tire pressure warning system may not oper-
ate properly
The tire pressure warning system will be disabled in the following condi-
tions:
(When the condition becomes normal, the system will work properly.)
●If tires not equipped with 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.
●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 similar frequencies 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 th e vehicle, in particular 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.
■Initializing the tire pressure warning system
Initialize the system with the tire infl ation pressure adjusted to the speci-
fied level.
■If you press the tire pressure warning reset switch accidentally
If initialization is perform ed, adjust the 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 following
cases, the settings ha s not been recorded and the system will not operate
properly. If repeated attempts to record tire inflation pressure settings are
unsuccessful, have the vehicle in spected by your Toyota dealer.
●When operating the tire pressure wa rning reset switch, the tire pressure
warning light does not blink 3 times.
●After driving for a certain period of time since the initialization has been
completed, the warning light comes on after blinking for 1 minute.

502
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7-3. Do-it-yourself maintenance
■Tire pressure warning system certification
FCC ID:GQ4-45T
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 ex pressly approved by the party
responsible for compliance could void the user’s authority to operate the
equipment.
For vehicles sold in Canada
NOTE:
Operation is subject to the following two conditions: (1) this device may
not cause interference, and (2) this device must accept any interference,
including interference that may cause undesired operation of the device.
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 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 b een used on another vehicle.
Do not use tires if you do not know how they were used previously.
●Vehicles with a compact spare tire: 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 warning reset switch without first
adjusting the tire inflation pressure 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 tire inflation pressure is
actually normal.

SIENNA_OM_OM08007U_(U)
5037-3. 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 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. Make sure to replace the tire pressure warning valve and
transmitter when replacing the tire. ( P. 497)
■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.