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336 2-4. Using other driving systems
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CAUTION
■When Enhanced 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 TRAC and VSC systems are turned off
Be especially careful and drive at a speed appropriate to the road condi-
tions. As these are the systems to ensure vehicle stability and driving force,
do not turn the TRAC and VSC systems off unless necessary.
■ Replacing tires
Make sure that all tires are of the specified size and of the same brand, tread
pattern and total load capacity. In addition, make sure that the tires are
inflated to the recommended tire pressure level.
The ABS and Enhanced 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 malfunction.
■ Active Torque Control 4WD system
●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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369
2-5. Driving information
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When driving
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Winter driving tips
Carry out the necessary preparations and inspections before driving
the vehicle in winter. Always drive the vehicle in a manner appropri-
ate to the prevailing weather conditions.
■ Pre-winter preparations
●Use fluids that are appropriate to the prevailing outside tem-
peratures.
• Engine oil
• Engine coolant
• Washer fluid
● Have a service technician inspect the level and specific grav-
ity of battery electrolyte.
● Have the vehicle fitted with four snow tires or purchase a set
of tire chains for the front tires.
Ensure that all tires are the same size and brand, and that chains
match the size of the tires.
■Before driving the vehicle
Perform the following according to the driving conditions:
●Do not try to forcibly open a window or move a wiper that is
frozen. Pour warm water over the frozen area to melt the ice.
Wipe away the water immediately to prevent it from freezing.
● To ensure proper operation of th e climate control system fan,
remove any snow that has accumulated on the air inlet vents
in front of the windshield.
● Remove any ice that has accumu lated on the vehicle chassis.
● Periodically check for and remove any excess ice or snow
that may have accumulated in the wheel well or on the
brakes.
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370 2-5. Driving information
SIENNA_OM_OM45483U_(U)
Selecting tire chainsUse 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 on the use of tire chains
Regulations regarding the use of ti re chains vary depending on loca-
tion and type of road. Always chec k local regulations before installing
chains.
■ When driving the vehicle
Accelerate the vehicle slowly and drive at a reduced speed suit-
able to road conditions.
■ When parking the vehicle
Park the vehicle and move the shift lever to P without setting the
parking brake. The parking brak e may freeze up, preventing it
from being released. If necessary , block the wheels to prevent
inadvertent sliding or creeping.
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371
2-5. Driving information
2
When driving
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■
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.
CAUTION
■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 size specified.
● 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.
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690 4-3. Do-it-yourself maintenance
SIENNA_OM_OM45483U_(U)
Installing tire pressure warning valves and transmittersWhen 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 regi stered in the tire pressure warn-
ing computer and the tire pressure warning system must be initial-
ized. Have tire pressure warning valve and transmitter ID codes
registered by your Toyota dealer. ( P. 692)
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 syst em 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 pl ace and turn the engine switch
(vehicles without a smart key system) or the “ENGINE START
STOP” switch (vehicles with a smart key system) off.
Initialization cannot be performed while the vehicle is moving.
Adjust the tire inflation pressure to the specified cold tire infla-
tion pressure level. ( P. 807)
Make sure to adjust the tire pressure to the specified cold tire
inflation pressure level. The ti re pressure warning system will
operate based on this pressure level.
STEP1
STEP2
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692 4-3. Do-it-yourself maintenance
SIENNA_OM_OM45483U_(U)
Registering ID codesThe 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 regi ster the ID code. Have the ID code
registered by your Toyota dealer.
■When to replace your vehicle’s tires
Tires should be replaced if:
●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 c annot 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
registered, the tire pre ssure 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.
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694 4-3. Do-it-yourself maintenance
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■Tire types
1 Summer tiresSummer tires are high-speed performance tires best suited to highway
driving under dry conditions. Sinc e summer tires do not have the same
traction performance as snow tire s, summer tires are inadequate for
driving on snow-covered or icy roads. For driving on snow-covered
roads or icy roads, the use of snow tires is recommended. When
installing snow tires, be sure to replace all four tires.
2 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
compared with summer tires in highway driving.
3Snow 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. 369)
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697
4-3. Do-it-yourself maintenance
4
Maintenance and care
SIENNA_OM_OM45483U_(U)
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.