
SIENNA_OM_OM08007U_(U)
3054-5. Using the driving support systems
4
Driving
■Conditions that may trigger the system even if there is no possibility of a
collision
In any of the following situations where the frontal area of the radar sensor is
interrupted, the radar sensor may detect possibility of a frontal collision and
the system may be activated.
●When passing by an oncoming vehicle in a curve or a turn to the right or the
left.
● When rapidly approaching an obstacle ahead (e.g. preceding vehicle, toll
gate barrier, etc.)
● When there is a structural object (billboard, low ceiling, fluorescent light,
etc.) above the uphill road ahead
● When driving on a narrow road or through under a low overhead structure
(bridge, tunnel, fly-under, etc.)
● When driving on an uneven road surface
● When there is a metal object, bump, or protrusion on the road surface
● When vehicle’s front part is raised or lowered depending on loading condi-
tions
● When the direction of radar sensor is misaligned by strong impact applied
on an area around the radar sensor, etc.
● When there is an obstacle (guard rail, etc.) by the roadside at the entrance
to a curve
● When the front of your vehicle is pointing upwards (caused by towing a
trailer, during emergency towing or putting a heavy load in the luggage com-
partment etc.)
When the system is activated in the situations described above, there is also
a possibility that the seat belts will retract quickly and the brakes may be
applied with a force greater than normal. When the seat belt is locked in the
retracted position, stop the vehicle in a safe place, release the seat belt and
refasten it.
■ Obstacles not detected
The sensor cannot detect plastic obstacles such as traffic cones. There may
also be occasions when the radar sens or cannot detect pedestrians, animals,
bicycles, motorcycles, trees, or snowdrifts.
■ Situations in which the pre-collis ion system does not function properly
The system may not function effectively in situations such as the following:
● On roads with sharp bends or uneven surfaces
● If a vehicle suddenly moves in front of your vehicle, such as at an intersec-
tion
● If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
● In inclement weather such as heavy rain, fog, snow or sand storms
● When your vehicle is skidding with the VSC system off
● When the axis of the radar is out of adjustment
● When an extreme change in vehicle height occurs

SIENNA_OM_OM08007U_(U)
3074-5. Using the driving support systems
4
Driving
WARNING
■Limitations of the pre-collision system
The driver is solely responsible for safe driving. Always drive safely, taking
care to observe your surroundings.
Do not use the pre-collision system instead of normal braking operations
under any circumstances. This system will not prevent collisions or lessen
damage or injuries in all cases. Do not overly rely on this system.
Failure to do so may cause an accident, resulting in death or serious injury.
This system has been designed to help avoid and reduce the impact of col-
lisions. However, the system operates differently depending on the situation
(P. 304, 305). As a result, the same level of performance may not be
expected in all cases. Also, the pre-collision brakes may not operate if the
driver is depressing the brake pedal or turning the steering wheel, as the
system will determine such conditions as collision avoidance operations.
■ Cautions regarding the assi st contents of the system
By means of alarms and brake control, the pre-collision system is intended
to assist the driver in avoiding collisions through the process of LOOK-
JUDGE-ACT.
There are limits to the degree of assistance the system can provide, so
please keep in mind the following important points.
● Assisting the driver in watching the road
The pre-collision system is only able to detect obstacles directly in front of
the vehicle, and only within a limited range. It is not a mechanism that
allows careless or inattentive driving, and it is not a system that can assist
the driver in low-visibility conditions. It is still necessary for the driver to
pay close attention to the vehicle’s surroundings.
● Assisting the driver in making correct judgment
When attempting to estimate the possibility of a collision, the only data
available to the pre-collision system is that from obstacles it has detected
directly in front of the vehicle. Therefore, it is absolutely necessary for the
driver to remain vigilant and to determine whether or not there is a possi-
bility of collision in any given situation.
● Assisting the driver in taking action
The pre-collision system’s braking assist feature is designed to help
reduce the severity of a collision, and so only acts when the system has
judged that a collision is unavoidable. This system is not capable of auto-
matically avoiding a collision or bringing the vehicle to a stop safely with-
out appropriate operations performed by the driver. For this reason, when
encountering a dangerous situation the driver must take direct and imme-
diate action in order to ensure the safety of all involved.

308
SIENNA_OM_OM08007U_(U)
4-5. Using the driving support systems
WARNING
■When the sensor may not be correct ly detecting the vehicle ahead
Apply the brakes as necessary in any of the following situations.
● When water or snow thrown up by the surrounding vehicles hinders the
functioning of the sensor
● When your vehicle is pointing upwards (caused by a heavy load in the lug-
gage compartment etc.)
● Vehicles that cut in suddenly
● Vehicles with small rear ends (trailers with no load on board etc.)
● Motorcycles traveling in the same lane
■ Handling the radar sensor
Observe the following to ensure the pre-collision system can function effec-
tively:
●Keep the sensor and front grille clean at all times.
Clean the sensor and front grille with a soft cloth so you do not mark or
damage them.
● Do not subject the sensor or surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may become
inaccurate or malfunction. If the sensor or surrounding area is subject to a
strong impact, always have the area inspected and adjusted by your Toy-
ota dealer.
● Do not disassemble the sensor.
● Do not attach accessories or stickers to the sensor, grille or surrounding
area.
● Do not modify or paint the sensor and grille cover.
● If the sensor needs to be replaced, contact your Toyota dealer.

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SIENNA_OM_OM08007U_(U)
4-6. Driving tips
4
Driving
Winter driving tips
●Use fluids that are appropriate to the prevailing outside tempera-
tures.
• Engine oil
• Engine coolant
• Washer fluid
● Have a service technician ins pect the condition of the battery.
● 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.
Perform the following accordin g 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 the climate control system fan,
remove any snow that has accumulated on the air inlet vents in
front of the windshield.
● Check for and remove any excess ice or snow that may have accu-
mulated on the exterior lights, ve hicle’s roof, chassis, around the
tires or on the brakes.
● Remove any snow or mud from the bottom of your shoes before
getting in the vehicle.
Carry out the necessary preparations and inspections before
driving the vehicle in winter. Always drive the vehicle in a man-
ner appropriate to the prevailing weather conditions.
Preparation for winter
Before driving the vehicle

318
SIENNA_OM_OM08007U_(U)
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

470
SIENNA_OM_OM08007U_(U)
7-1. Maintenance and care
NOTICE
■To prevent paint deterioration and corrosion on the body and compo-
nents (aluminum wheels etc.)
● Wash the vehicle immediately in the following cases:
• After driving near the sea coast
• After driving on salted roads
• If coal tar or tree sap is present on the paint surface
• If you see dead insects, insect droppings or bird droppings on the paint
• After driving in an area contaminated with soot, oily smoke, mine dust,
iron powder or chemical substances
• If the vehicle becomes heavily soiled in dust or mud
• If liquids such as benzene and gasoline are spilled on the paint surface
● If the paint is chipped or scratched, have it repaired immediately.
● To prevent the wheels from corroding, remove any dirt and store in a place
with low humidity when storing wheels.
■ Cleaning the exterior lights
●Wash carefully. Do not use organic substances or scrub with a hard brush.
This may damage the surface of the lights.
● Do not apply wax on the surfaces of the lights.
Wax may cause damage to the lenses.
■ When using an automatic car wash (vehicles with rain-sensing wind-
shield wipers)
Set the wiper switch to the off position. If the wiper switch is in “AUTO”, the
wipers may operate and the wiper blades may be damaged.
■ When using a high pressure car wash
Do not bring the nozzle tip close to boots (rubber or resin manufactured
cover), connectors or the following parts. The parts may be damaged if they
come into contact with high-pressure water.
• Traction related parts
• Steering parts
• Suspension parts
• Brake parts

477
SIENNA_OM_OM08007U_(U)
7-2. Maintenance
7
Maintenance and care
General maintenance
Listed below are the general maintenance items that should be
performed at the intervals specified in the “Owner’s Warranty
Information Booklet” or “Owner’s Manual Supplement/Sched-
uled Maintenance Guide”. It is recommended that any problem
you notice should be brought to the attention of your Toyota
dealer or qualified service shop for advice.
Engine compartment
ItemsCheck points
BatteryCheck connections. (P. 492)
Brake fluidIs the brake fluid at the correct level?
(P. 491)
Engine coolantIs the engine coolant at the correct
level? (P. 489)
Engine oilIs the engine oil at the correct level?
(P. 487)
Exhaust systemThere should not be any fumes or strange
sounds.
Radiator/condenserThe radiator and condenser should be free
from foreign objects. (P. 491)
Washer fluidIs there sufficient washer fluid? ( P. 495)

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SIENNA_OM_OM08007U_(U)
7-2. Maintenance
Vehicle interior
ItemsCheck points
Accelerator pedal • The accelerator pedal should move
smoothly (without uneven pedal effort or
catching).
Automatic transaxle “Park”
mechanism• When parked on a slope with the shift
lever in P, is the vehicle securely
stopped?
Brake pedal
• Does the brake pedal move smoothly?
• Does the brake pedal have appropriateclearance from the floor? ( P. 606)
• Does the brake pedal have the correct amount of free play? ( P. 606)
Brakes
• The vehicle should not pull to one side
when the brakes are applied.
• The brakes should work effectively.
• The brake pedal should not feel spongy.
• The brake pedal should not get too close to the floor when the brakes are applied.
Head restraints• Do the head restraints move smoothlyand lock securely?
Indicators/buzzers• Do the indicators and buzzers function
properly?
Lights• Do all the lights come on?
• Are the headlights aimed correctly?
Parking brake
• Does the parking brake lever or pedalmove smoothly?
• When parked on a slope with the parking brake on, is the vehicle securely
stopped?
Seat belts• Do the seat belts operate smoothly?
• The seat belts should not be damaged.
Seats• Do the seat controls operate properly?
Steering wheel
• Does the steering wheel rotatesmoothly?
• Does the steering wheel have the correct amount of free play?
• There should not be any strange sounds
coming from the steering wheel.