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SIENNA_U (OM45477U)
■Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from
overheating when there is frequent steering input over an extended period of
time. The steering wheel may feel heavy as a result. Should this occur,
refrain from excessive steering input or stop the vehicle and turn the engine
off. The EPS system should return to normal within 10 minutes.
CAUTION
■ABS does not operate effectively when
● Tires with inadequate gripping ability are used (such as excessively worn
tires on a snow covered road).
● The vehicle hydroplanes while driving at high speed on wet or slick roads.
■ Stopping distance when ABS is oper ating may exceed that of normal
conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always
maintain a safe distance from the vehicle in front of you in the following situ-
ations.
● When driving on dirt, gravel or snow-covered roads
● When driving with tire chains
● When driving over bumps in the road
● When driving over roads with potholes or roads with uneven surfaces
■ TRAC may not operate effectively when
Directional control and power may not be achievable while driving on slip-
pery road surfaces, even if the TRAC system is operating.
Do not drive the vehicle in conditions where stability and power may be lost.
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332 2-4. Using other driving systems
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CAUTION
■When Enhanced VSC is activated
The slip indicator light flashes and a warning buzzer sounds. Always drive
carefully. Reckless driving may cause an accident. Exercise particular care
when the indicator light flashes and a buzzer sounds.
■ 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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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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When driving
SIENNA_U (OM45477U)
Selecting tire chains
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 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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354 2-5. Driving information
SIENNA_U (OM45477U)
■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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When driving
SIENNA_U (OM45477U)
●
Reversing with a trailer attached is difficult and requires practice.
Grip the bottom of the steering wheel and move your hand to the
left to move the trailer to the left. Move your hand to the right to
move the trailer to the right. (Thi s is generally opposite to reversing
without a trailer attached.) Avoid sharp or prolonged turning. Have
someone guide you when reversing to reduce the risk of an acci-
dent.
● As stopping distance is increased when towing a trailer, vehicle-to-
vehicle distance should be increased. For each 10 mph (16 km/h) of
speed, allow at least one vehicle and trailer length.
● Avoid sudden braking as you may skid, resulting in the trailer jack-
knifing and a loss of vehicle control. This is especially true on wet
or slippery surfaces.
● Avoid jerky starts or sudden acceleration.
● Avoid jerky steering and sharp turns, and slow down before mak-
ing a turn.
● Note that when making a turn, th e trailer wheels will be closer than
the vehicle wheels to the inside of the turn. Compensate by making
a wider than normal turning radius.
● Slow down before making a turn, in crosswinds, on wet or slippery
surfaces, etc.
Increasing vehicle speed can destabilize the trailer.
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●
Always place wheel blocks under both the vehicle’s and the
trailer’s wheels when parking. Ap ply the parking brake firmly, and
put the transmission in P. Avoid pa rking on a slope, but if unavoid-
able, do so only after performing the following:
Apply the brakes and keep them applied.
Have someone place wheel blo cks under both the vehicle’s
and trailer’s wheels.
When the wheel blocks are in pl ace, release the brakes slowly
until the blocks absorb the load.
Apply the parking brake firmly.
Shift into P and turn off the engine.
● When restarting after parking on a slope:
With the transmission in P, start the engine. Be sure to keep
the brake pedal pressed.
Shift into a forward gear. If reversing, shift into R.
Release the parking brake and brake pedal, and slowly pull or
back away from the wheel blocks. Stop and apply the brakes.
Have someone retrieve the blocks.
STEP1
STEP2
STEP3
STEP4
STEP5
STEP1
STEP2
STEP3
STEP4
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When driving
SIENNA_U (OM45477U)
■
Break-in schedule
If your vehicle is new or equipped with any new power train components
(such as an engine, transmission, differential or wheel bearing), Toyota rec-
ommends that you do not tow a trailer until the vehicle has been driven \
for
over 500 miles (800 km).
After the vehicle has been driven for over 500 miles (800 km), you can s\
tart
towing. However, for the next 500 miles (800 km), drive the vehicle at a
speed of less than 50 mph (80 km/h) when towing a trailer, and avoid full
throttle acceleration.
■ Maintenance
● If you tow a trailer, your vehicle will require more frequent maintenance
due to the additional load. (See “Scheduled Maintenance Guide” or
“Owner’s Manual Supplement”.)
● Retighten the fixing bolts of the towing ball and bracket after approxi-
mately 600 miles (1000 km) of trailer towing.