2017 TOYOTA SIENNA brakes

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2754-5. Using the driving support systems
4
Driving
WARNING
■Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set speed. If automatic deceleration/acceleration is not
appropriate, adjust the vehicle speed, as well as the distance between your
vehicle and vehicles ahead by applying the brakes, etc.
■ Cautions regarding the driving assist systems
Observe the following precautions.
Failure to do so may cause an accident resulting in death or serious injury.
●Assisting the driver to measure following distance
The dynamic radar cruise control is only intended to help the driver in
determining the following distance between the driver’s own vehicle and a
designated vehicle travelling ahead. 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 driver to pay close
attention to the vehicle’s surroundings.
● Assisting the driver to judge proper following distance
The dynamic radar cruise control determines whether the following dis-
tance between the driver’s own vehicle and a designated vehicle travelling
ahead is appropriate or not. It is not capable of making any other type of
judgement. Therefore, it is absolutely necessary for the driver to remain
vigilant and to determine whether or not there is a possibility of danger in
any given situation.
● Assisting the driver to operate the vehicle
The dynamic radar cruise control has no capability to prevent or avoid a
collision with a vehicle travelling ahead. Therefore, if there is ever any
danger, the driver must take immediate and direct control of the vehicle
and act appropriately in order to ensure the safety of all involved.
■ To avoid inadvertent cr uise control activation
Switch the cruise control off using the “ON-OFF” button when not in use.

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■The intuitive parking assist can be operated when
●The engine switch is in the “ON” position (vehicles without a smart key sys-
tem) or IGNITION ON mode (vehicles with a smart key system).
● Front corner sensors:
• The shift lever is not in P.
• The vehicle speed is approximately 6 mph (10 km/h) or less.
● Rear corner and rear center sensors:
The shift lever is in R.
■ Intuitive parking assist display
When an obstacle is detected while the rear view monitor system is in use,
the warning indicator will appear in the upper corner of the screen even if the
display setting has been set to off.
■ Sensor detection information
●The sensor’s detection areas are limited to the areas around the vehicle’s
bumper.
● Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where
this may occur are listed below.
• There is dirt, snow or ice on the sensor. (Wiping the sensors will resolve
this problem.)
• The sensor is frozen. (Thawing the area will resolve this problem.)
In especially cold weather, if a sensor is frozen the screen may show an
abnormal display, or obstacles may not be detected.
• The sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle
engines, air brakes of large vehicles, or other loud noises producing ultra-
sonic waves.
• There is another vehicle equipped with parking assist sensors in the
vicinity.
• The sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather
• The area directly under the bumpers is not detected.
• If obstacles draw too close to the sensor.
• A non-genuine Toyota suspension (lowered suspension etc.) is installed.
• People may not be detected if they are wearing certain types of clothing.
In addition to the examples above, there are instances in which, because of
their shapes, signs and other objects may be judged by the sensor to be
closer than they are.

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Driving
Driving assist systems
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied suddenly,
or if the brakes are applied while driving on a slippery road surface
◆Brake assist
Generates an increased level of braking force after the brake pedal
is depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or
turning on slippery road surfaces
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from
spinning when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control (if equipped)
Helps to prevent the vehicle from rolling backward when starting on
an incline or slippery slope
◆EPS (Electric Power Steering)
Employs an electric motor to redu ce the amount of effort needed to
turn the steering wheel
◆Active Torque Control 4WD (AWD models only)
Automatically switches from front-wheel drive to AWD (All-Wheel
Drive) according to driving condit ions, helping to ensure reliable
handling and stability. Examples of conditions where the system will
switch to AWD are when cornering, going uphill, starting off or
accelerating, and when the road surface is slippery due to snow or
rain etc.
To help enhance driving safety and performance, the following
systems operate automatically in response to various driving
situations. Be aware, however, that these systems are supple-
mentary and should not be relied upon too heavily when operat-
ing the vehicle.

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◆VDIM (Vehicle Dynamics Integr ated Management) (if equipped)
Provides integrated control of the ABS, brake assist, TRAC, VSC,
hill-start assist cont rol, and EPS systems
Helps to maintain vehicle stabilit y when swerving on slippery road
surfaces by controlling the brakes and engine output
◆PCS (Pre-Collision System) (if equipped)
 P. 3 0 2
The slip indicator light will flash
while the TRAC/VSC systems are
operating.
If the vehicle gets stuck in mud, dirt or snow, the TRAC system may
reduce power from the engine to the wheels. Pressing to turn the
system off may make it easier for you to rock the vehicle in order to
free it.
To turn the TRAC system off,
quickly press and release .
The “Traction Control OFF”/“TRAC
OFF” will be shown on the multi-
information display.
Press again to turn the system
back on.
When the TRAC/VSC systems are operating
Disabling TRAC system

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PCS (Pre-Collision System)
◆Pre-collision warning
When a high possibility of a
frontal collision is detected, the
pre-collision system warning
light flashes, a buzzer sounds
and a message is shown on the
multi-information display to
urge the driver to take evasive
action.
◆Pre-collision seat belts (front seat belts only)
If the pre-collision sensor detects that a collision is unavoidable, the
pre-collision system will retract the seat belt before the collision
occurs. The same will happen if the driver makes an emergency
braking or loses control of the vehicle. ( P. 3 1 )
However, when the VSC system is disabled, the system will not
operate in the event of skidding.
◆Pre-collision brake assist
When there is a high po ssibility of a frontal collision, the system
applies greater braking force in relation to how strongly the brake
pedal is depressed.
The system may not warn the driver using a warning light, warning
display and buzzer when the system detects and judges braking
operations.
: If equipped
When the radar sensor detects pos sibility of a frontal collision,
the pre-collision system such as the brakes and seat belts are
automatically engaged to lessen impact as well as vehicle dam-
age.

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Driving
◆Pre-collision braking
When there is a high po ssibility of a frontal collision, the system
warns the driver using a warning light, warning display and buzzer.
If the system determines that a collision is unavoidable, the brakes
are automatically applied to redu ce the collision speed. Pre-colli-
sion braking can be disabled usin g the pre-collision braking off
switch.
Pre-collision braking disabled
Pre-collision braking enabled
The pre-collision system warning
light will turn on when pre-collision
braking is disabled.
The radar sensor detects vehi-
cles or other obstacles on or near
the road ahead and determines
whether a collision is imminent
based on the position, speed, and
heading of the obstacles.
Disabling pre-collision braking
1
2
Radar sensor

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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

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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.