SIENNA_OM_OM08007U_(U)
3014-5. Using the driving support systems
4
Driving
WARNING
■TRAC may not operat e effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRAC system is operating.
Drive the vehicle carefully in conditions where stability and power may be
lost.
■ Hill-start assist control (vehicles with a hill-start assist control system)
●Do not overly rely on hill-start assist control. Hill-start assist control may
not operate effectively on steep inclines and roads covered with ice.
● Unlike the parking brake, hill-start assist control is not intended to hold the
vehicle stationary for an extended period of time. Do not attempt to use
hill-start assist control to hold the vehicle on an incline, as doing so may
lead to an accident.
■ When the VSC is activated
The slip indicator light flashes. Always drive carefully. Reckless driving may
cause an accident. Exercise particular care when the indicator light flashes.
■ When the TRAC/VSC syst ems are turned off
Be especially careful and drive at a speed appropriate to the road condi-
tions. As these are the systems to help ensure vehicle stability and driving
force, do not turn the TRAC/VSC systems off unless necessary.
■
Replacing tires
Make sure that all tires are of the specified size, brand, tread pattern
and total load capacity. In addition, make sure that the tires are inflated
to the recommended tire inflation pressure level.
The ABS, TRAC and VSC systems will not function correctly if different
tires are installed on the vehicle.
Contact your Toyota dealer for further information when replacing tires
or wheels.
■Handling of tires and suspension
Using tires with any kind of problem or modifying the suspension will
affect the driving assist systems, and may cause the system to malfunc-
tion.
■ Active Torque Control 4WD system (AWD models only)
●The AWD system of this vehicle is intended to ensure driving stability on
normal roads. It is not designed for use in demanding situations such as
rally driving.
● Take care when driving on slippery road surfaces.
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4-6. Driving tips
Accelerate the vehicle slowly, keep a safe distance between you and
the vehicle ahead, and drive at a reduced speed suitable to road con-
ditions.
●Park the vehicle and move the shift lever to P without setting the
parking brake. The parking brake may freeze up, preventing it from
being released. If the vehicle is parked without setting the parking
brake, make sure block the wheels.
Failure to do so may be dangerous because it may cause the vehi-
cle to move unexpectedly, pos sibly leading to an accident.
● If the vehicle is parked without setting the parking brake, confirm
that the shift lever cannot be moved out of P
*.
*: The shift lever will be locked if it is attempted to be shifted from P to any
other position without depressing the brake pedal. If the shift lever can be
shifted from P, there may be a problem with the shift lock system. Have the
vehicle inspected by your Toyota dealer immediately.
Use the tire chains of correct size and type.
Use SAE Class “S” type radial tire chains, with the exception of radial
cable chains or V-bar type chains.
Regulations regarding the use of tire chains vary depending on loca-
tion and type of road. Al ways check local regulations before installing
chains.
■ Tire chain installation
Observe the following precautions when installing and removing chains.
●Install and remove tire chains in a safe location.
● Install tire chains on the front tires only. Do not install tire chains on the rear
tires.
● Install tire chains on front tires as tightly as possible. Retighten chains after
driving 1/4 - 1/2 mile (0.5 - 1.0 km).
● Install tire chains following the instructions provided with the tire chains.
When driving the vehicle
When parking the vehicle
Selecting tire chains
Regulations on the use of tire chains
SIENNA_OM_OM08007U_(U)
3194-6. Driving tips
4
Driving
WARNING
■Driving with snow tires
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in a loss of vehicle control and cause death or
serious injury.
●Use tires of the specified size.
● Maintain the recommended level of air pressure.
● Do not drive in excess of 75 mph (120 km/h), regardless of the type of
snow tires being used.
● Use snow tires on all, not just some wheels.
■ Driving with tire chains
Observe the following precautions to reduce the risk of accidents.
Failing to do so may result in the vehicle being unable to be driven safely,
and may cause death or serious injury.
●Do not drive in excess of the speed limit specified for the tire chains being
used or 30 mph (50 km/h), whichever is lower.
● Avoid driving on bumpy road surfaces or over potholes.
● Avoid sudden acceleration, abrupt steering, sudden braking and shifting
operations that cause sudden engine braking.
● Slow down sufficiently before entering a curve to ensure that vehicle con-
trol is maintained.
NOTICE
■Repairing or replacing snow tires
Request repairs or replacement of snow tires from Toyota dealers or legiti-
mate tire retailers.
This is because the removal and attachment of snow tires affects the opera-
tion of the tire pressure warning valves and transmitters.
■ Fitting tire chains
The tire pressure warning valves and transmitters may not function correctly
when tire chains are fitted.
SIENNA_OM_OM08007U_(U)
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
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2
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SIENNA_OM_OM08007U_(U)
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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SIENNA_OM_OM08007U_(U)
7-3. Do-it-yourself maintenance
■Tire types
●Summer tires
Summer tires are high-speed performance tires best suited to highway
driving under dry conditions. Since summer tires do not have the same
traction performance as snow tires, summer tires are inadequate for
driving on snow-covered or icy ro ads. For driving on snow-covered
roads or icy roads, the use of snow tires is recommended. When install-
ing snow tires, be sure to replace all four tires.
●All season tires
All season tires are designed to provide better traction in snow and to
be adequate for driving in most winter conditions, as well as for use
year round. All season tires, however, do not have adequate traction
performance compared with snow tires in heavy or loose snow. Also, all
season tires fall short in acceleration and handling performance com-
pared with summer tires in highway driving.
●Snow tires
For driving on snow-covered roads or icy roads, we recommend using
snow tires. If you need snow tires, select tires of the same size, con-
struction and load capacity as the or iginally installed tires. Since your
vehicle has radial tires as original equipment, make sure your snow
tires also have radial construction. Do not install studded tires without
first checking local regulations for possible restriction. Snow tires
should be installed on all wheels. ( P. 317)
■If the tread on snow tires wears down below 0.16 in. (4 mm)
The effectiveness of the tire s as snow tires is lost.
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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. 497)
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