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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 width 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 have 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 after driving 1000 miles (1600 km).
● Be careful not to damage the aluminum wheels when using tire
chains.
● Use only Toyota genuine balance weights or equivalent and a plas-
tic or rubber hammer when balancing your wheels.
■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 advanced 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. 489)
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
WARNING
■When replacing wheels
●Do not use wheels that are a different size from those recommended 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 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.
■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.
NOTICE
■Replacing tire pressure warning valves and transmitters
●Because tire repair or replacement may affect the tire pressure warn-
ing valves and transmitters, make sure to have tires serviced by your
Toyota dealer or other qualified service shop. In addition, make sure to
purchase your tire pressure warning valves and transmitters at your
Toyota dealer.
●Ensure that only genuine Toyota wheels are used on your vehicle.
Tire pressure warning valves and transmitters may not work properly
with non-genuine wheels.
●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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SIENNA_OM_01999-08001_(U)
5057-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■Removed battery and other parts
These parts are small and if swallowed by a child, they can cause choking.
Keep away from children. Failure to do so could result in death or serious
injury.
NOTICE
■For normal operation after replacing the battery
Observe the following precautions to prevent accidents.
● Always work with dry hands.
Moisture may cause the battery to rust.
● Do not touch or move any other components inside the remote control.
● Do not bend either of the battery terminals.
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7-3. Do-it-yourself maintenance
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may
need replacement. ( P. 509)
● If the replaced fuse blows again, have the vehicle inspected by your Toyota
dealer.
■ If there is an overload in the circuit
The fuses are designed to blow, protecting the wiring harness from damage.
■ When replacing light bulbs
Toyota recommends that you use genuine Toyota products designed for this
vehicle. Because certain bulbs are connected to circuits designed to prevent
overload, non-genuine parts or parts not designed for this vehicle may be
unusable.
WARNING
■To prevent system breakdowns and vehicle fire
Observe the following precautions.
Failing to do so may cause damage to the vehicle, and possibly a fire or
injury.
● Never use a fuse of a higher amperage rating than that indicated, or use
any other object in place of a fuse.
● Always use a genuine Toyota fuse or equivalent.
Never replace a fuse with a wire, even as a temporary fix.
● Do not modify the fuses or fuse boxes.
NOTICE
■Before replacing fuses
Have the cause of electrical overload determined and repaired by your Toy-
ota dealer as soon as possible.
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5257-3. Do-it-yourself maintenance
7
Maintenance and care
WARNING
■Replacing light bulbs
● Turn off the lights. Do not attempt to replace the bulb immediately after
turning off the lights.
The bulbs become very hot and may cause burns.
● Do not touch the glass portion of the light bulb with bare hands. When it is
unavoidable to hold the glass portion, use and hold with a clean dry cloth
to avoid getting moisture and oils on the bulb. Also, if the bulb is scratched
or dropped, it may blow out or crack.
● Fully install light bulbs and any parts used to secure them. Failure to do so
may result in heat damage, fire, or water entering the headlight unit. This
may damage the headlights or cause condensation to build up on the lens.
● Do not attempt to repair or disassemble the bulb, socket, electrical wiring,
or sub components. This may cause serious injury due to electric shock.
●Vehicles with discharge headlights:
While the low beam headlights are
turned on, and for a short time after they
have been turned off, metal compo-
nents at the rear of the headlight
assembly will be extremely hot. To pre-
vent burns, do not touch these metal
components until you are certain they
have cooled down.
Metal components
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7-3. Do-it-yourself maintenance
WARNING
■Discharge headlights (if equipped)
● Contact your Toyota dealer before replacing the discharge headlights
(including light bulbs).
● Do not touch the discharge headlight’s high voltage socket when the head-
lights are turned on.
An extremely high voltage of 30000 V will be discharged and could result
in serious injury or death by electric shock.
● Do not attempt to take apart or repair the low beam headlight bulbs, con-
nectors, power supply circuits, or related components.
Doing so could result in electric shock and death or serious injury.
■ When replacing the rear turn signal lights or stop/tail lights
Inspect the gasket for any damage (rip, tear, hole, etc.). If there is any dam-
age, please contact your Toyota dealer and have the gasket replaced.
Improper installation of the gasket may result in water entering the rear light
unit.
■ To prevent damage or fire
● Make sure bulbs are fully seated and locked.
● Check the wattage of the bulb before installing to prevent heat damage.
NOTICE
■When installing the back door trim
To prevent damage, be careful not to pinch any of the wire harnesses or
connectors with the back door trim.
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8When trouble arises
8-1. Essential informationEmergency flashers .......... 528
If your vehicle has to be stopped in an
emergency ...................... 529 8-2. Steps to take in an
emergency
If your vehicle needs to be towed ......................... 531
If you think something is wrong .............................. 535
Fuel pump shut off system ............................ 536
If a warning light turns on or a warning buzzer
sounds ............................ 537
If a warning message is displayed......................... 546
If you have a flat tire (vehicles with
run-flat tires).................... 562
If you have a flat tire (vehicles with a compact
spare tire)........................ 564
If the engine will not start ................................. 578
If the shift lever cannot be shifted from P............. 580
If the electronic key does not operate properly
(vehicles with a smart
key system)..................... 581
If the battery is discharged ...................... 583
If your vehicle overheats ... 587
If the vehicle becomes stuck ............................... 590
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5308-1. Essential information
SIENNA_OM_01999-08001_(U)
WARNING
■If the engine has to be turned off while driving
● Power assist for the brakes and steering wheel will be lost, making the
brake pedal harder to depress and the steering wheel heavier to turn.
Decelerate as much as possible before turning off the engine.
● Vehicles without a smart key system: Never attempt to remove the key, as
doing so will lock the steering wheel.