2017 TOYOTA SIENNA Owners Manual

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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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Driving
■Turning off both TRAC and VSC systems
To turn the TRAC and VSC systems off, press and hold for more than 3
seconds while the vehicle is stopped.
The VSC OFF indicator light will come on and the “Traction Control OFF”/
“TRAC OFF” will be shown on the multi-information display.
Press again to turn the systems back on.
■ When the message is displayed on th e multi-information display show-
ing that TRAC has been disable d even if has not been pressed
TRAC and hill-start assist control (if equipped) cannot be operated. Contact
your Toyota dealer.
■ Sounds and vibrations caused by ABS, brake assist, TRAC, VSC and
hill-start assist contro l (if equipped) systems
● A sound may be heard from the engine compartment when the brake pedal
is depressed repeatedly, when the engine is started or just after the vehicle
begins to move. This sound does not indicate that a malfunction has
occurred in any of these systems.
● Any of the following conditions may occur when the above systems are
operating. None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
• The brake pedal may pulsate slightly after ABS is activated.
• The brake pedal may move down slightly after ABS is activated.
■ EPS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
■ Automatic reactivation of TRAC and VSC systems
After turning the TRAC and VSC systems off, the systems will be automati-
cally re-enabled in the following situations:
● When the engine switch is turned to the “LOCK” position (vehicles without a
smart key system) or off (vehicles with a smart key system).
● If only the TRAC system is turned off, the TRAC will turn on when vehicle
speed increases
If both the TRAC and VSC systems are turned off, automatic re-enabling will
not occur when vehicle speed increases.

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■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.
■ Operating conditions of hill-start assist control (vehicles with a hill-start
assist control system)
When the following four conditions are met, the hill-start assist control will
operate:
●The shift lever is in a position other than P or N (when starting off forward/
backward on an upward incline).
● The vehicle is stopped.
● The accelerator pedal is not depressed.
● The parking brake is not applied.
■ Automatic system cancelation of hill-sta rt assist control (vehicles with a
hill-start assist control system)
The hill-start assist control will turn off in any of the following situations:
● The shift lever is shifted to P or N.
● The accelerator pedal is depressed.
● The parking brake is applied.
● Approximately 2 seconds elapse after the brake pedal is released.
WARNING
■ The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (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 the ABS is operating may exceed that of nor-
mal 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, especially in the
following situations:
● 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 uneven surfaces

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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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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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■The pre-collision system is operational when
● Pre-collision seat belts (type A):
• The front occupants are wearing a seat belt.
• Vehicle speed is greater than about 19 mph (30 km/h).
• The system detects sudden braking or skidding.
● Pre-collision seat belts (type B):
• The front occupants are wearing a seat belt.
• Vehicle speed is greater than about 4 mph (5 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 19 mph (30 km/h).
● Pre-collision braking:
• The pre-collision braking off switch is not pressed.
• Vehicle speed is greater than about 10 mph (15 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 10 mph (15 km/h).
● Pre-collision brake assist:
• Vehicle speed is greater than about 19 mph (30 km/h).
• The speed at which your vehicle is approaching the obstacle or the vehi-
cle running ahead of you is greater than about 19 mph (30 km/h).
• The brake pedal is depressed.