2021 TOYOTA SIENNA HYBRID brakes

2924-5. Using the driving support systems
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver.
Example of deceleration crui sing and follow-up cruising
When a preceding vehicle driving slower than the set speed
appears
When a vehicle is detected runni ng ahead of you, the system automatically
decelerates your vehicle. When a greater reduction in vehicle s peed is nec-
essary, the system applies the brakes (the stop lights will come on at this
time). The system will respond to changes i n the speed of the vehicle
ahead in order to maintain the ve hicle-to-vehicle distance set by the driver.
Approach warning warns you when the system cannot decelerate suffi-
ciently to prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you st ops, your vehicle will also stop (vehicle is
stopped by system control). Afte r the vehicle ahead starts off, pressing the
“+RES” switch or depressing the accelerator pedal (start-off operation) will
resume follow-up cruising. If the start-off operation is not performed, system
control continues to keep your vehicle stopped.
When the turn signal lever is ope rated and your vehicle moves to an over-
taking lane while driving at 50 mph (80 km/h) or more, the vehi cle will accel-
erate to help to overt ake a passing vehicle.
The system’s identifi cation of what is an overtaking lane may be deter-
mined solely based on the location of the steering wheel in the vehicle (left
side driver position versus righ t side driver position.) If the vehicle is driven
to a region where the overtaking lane is on a different side fr om where the
vehicle is normally driven, the v ehicle may accelerate when the turn signal
lever is operated in the opposite direction to the overtaking l ane (e.g., if the
driver normally operates the vehicle in a region where the over taking lane is
to the right but then drives to a region where the overtaking l ane is to the
left, the vehicle may accelerate when the right turn signal is activated).
Example of acceleration
When there are no longer any preceding vehicles driving slower
than the set speed
The system accelerates until the set speed is reached. The system then
returns to constan t speed cruising.
1Press the cruise control main switch to activate the cruise
control.
Dynamic radar cruise control indi-
cator will come on and a message
will be displayed on
the multi-infor-
mation display. Press the switch
A
B
C
Setting the vehicle speed
(vehicle-to-vehicle dis-
tance control mode)

3124-5. Using the driving support systems
sensor.
• There will be a short delay
between static object detection
and display (warning buzzer
sounds). Even at low speeds,
there is a possibilit y that the object
will come within approximately
11.9 in. (30 cm) before the display
is shown and the warning buzzer
sounds.
• It might be difficult to hear the buzzer due to the volume of the
audio system or air flow noise of
the air conditioning system.
• It may be difficult to hear the
sound of this system due to the
buzzers of other systems.
■Conditions under which the
function may not function cor-
rectly
Certain vehicle conditions and the
surrounding environment may affect
the ability of a sensor to correctly
detect objects. Particular instances
where this may occur are listed
below.
●There is dirt, snow or ice on a sen-
sor. (Cleaning the sensors will
resolve this problem.)
●A sensor is frozen. (Thawing the
area will resolve this problem.)
In especially cold weather, if a
sensor is frozen the sensor dis-
play may be displayed abnor-
mally, or objects, such as a wall,
may not be detected.
●A sensor is covered in any way.
●When a sensor or the area around
a sensor is extremely hot or cold.
●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 vehi-
cles, or other l oud noises produc-
ing ultrasonic waves.
●There is another vehicle equipped
with parking assist sensors in the
vicinity.
●A sensor is coated with a sheet of spray or heavy rain.
●If a sensor is hit by a large amount
of water, such as when driving on
a flooded road.
●If the vehicle is significantly tilted.
●The vehicle is approaching a tall
or curved curb.
●If objects draw too close to the
sensor.
■Objects which may not be prop-
erly detected
The shape of the object may pre-
vent the sensor from detecting it.
Pay particular atte ntion to the fol-
lowing objects:
●Wires, fences, ropes, etc.
●Cotton, snow and other materials
that absorb sound waves
●Sharply-angled objects
●Low objects
●Tall objects with upper sections
projecting outwards in the direc-
tion of your vehicle
People may not be detected if they
are wearing certain types of cloth-
ing.

3194-5. Using the driving support systems
4
Driving
*: If equipped
■Parking Support Brake
function (static objects)
 P.323
■Parking Support Brake
function (rear-crossing
vehicles)
 P.329
PKSB (Parking Sup-
port Brake)*
The Parking Support Brake
system consists of the fol-
lowing functions that oper-
ate when driving at a low
speed or backing up, such
as when parking. When the
system determines that the
possibility of a collision
with a detected object is
high, a warning operates to
urge the driver to take eva-
sive action. If the system
determines that the possi-
bility of a collision with a
detected object is extremely
high, the brakes are auto-
matically applied to help
avoid the collision or help
reduce the impact of the
collision.
PKSB (Parking Support
Brake) system
WARNING
■Limitations of the Parking
Support Brake system
Do not overly rely on the system,
as doing so may lead to an acci-
dent.
Always drive while checking the
safety of the surroundings of the
vehicle.
Depending on the vehicle and
road conditions, weather, etc., the
system may n ot operate.
The detection cap abilities of sen-
sors and radars are limited.
Always drive while checking the
safety of the surroundings of the
vehicle.
●The driver is solely responsible
for safe driving. Always drive
carefully, taking care to observe
your surroundings. The Parking
Support Brake system is
designed to provide support to
lessen the severity of collisions.
However, it may not operate in
some situations.
●The Parking Support Brake sys-
tem is not designed to stop the
vehicle comple tely. Addition-
ally, even if the system has
stopped the vehicle, it is neces-
sary to depress the brake pedal
immediately as brake control
will be canceled after approxi-
mately 2 seconds.
●Do not attempt to test the oper-
ation of the Parking Support
Brake system yourself.
Depending on the situations,
the system may not operate
properly, possibly leading to an
accident.

3214-5. Using the driving support systems
4
Driving
tion is necessary.
Audio system screen: “BRAKE!”
Multi-information display: “BRAKE!”
PKSB OFF indicator: Not illumi-
nated
Buzzer: Short beep
 Brake control is operating
The system determ ined that emer-
gency braking is necessary.
Audio system scr een: “BRAKE!”
Multi-information display: “BRAKE!”
PKSB OFF indicator: Not illumi-
nated
Buzzer: Short beep
 Vehicle stopped by system
operation
The vehicle has been stopped by
brake control operation.
Audio system screen: “Press Brake
Pedal”
Multi-information di splay: “Switch to
Brake” (If the accelerator pedal is
not depressed, “Brake” will be dis-
played.)
PKSB OFF indicator: Illuminated
Buzzer: Short beep
If the Parking Support Brake
determines that a collision with a
detected object is possible, the
hybrid system output will be
restricted to restrain any
increase in the vehicle speed.
(Hybrid system output restriction
control: See figure 2.)
Additionally, if the accelerator pedal continues to be
depressed, the brakes will be
applied automatically to reduce
the vehicle speed. (Brake con-
trol: See figure 3.)

Figure 1: When the PKSB
(Parking Support Brake) is not
operating
Hybrid system output
Braking force
Time
 Figure 2: When hybrid system
output restriction control oper-
ates
Hybrid system output
Braking force
Time
Hybrid system output restric-
tion control begins operating
System overview
A
B
C
A
B
C
D

3274-5. Using the driving support systems
4
Driving
tion of your vehicle
■Situations in which the Parking
Support Brake function (static
objects) may not operate
When the shift lever is in N
■Intuitive parking assist buzzer
Regardless of whether the intuitive
parking assist syste m is enabled or
not ( P.310), if the Parking Support
Brake function (static objects) is
enabled ( P.320), the front or rear
sensors detect an object and brake
control and hybrid system output
restriction control are performed, the
intuitive parking assist buzzer will
sound to notify the driver of the
approximate distanc e to the object.
■Situations in which the Parking
Support Brake function (static
objects) may operate even if
there is no possibility of a colli-
sion
In some situations, such as the fol-
lowing, the Parking Support Brake
function (static objects) may operate
even though there is no possibility of
a collision.
●Vehicle surroundings
• When driving on a narrow road
• When driving on a gravel road or in an area with tall grass
• When driving toward a banner, flag, low-hanging branch or boom
barrier (such as those used at rail-
road crossings, toll gates and
parking lots)
• When there is a structure on the roadside (such as when driving in
a narrow tunnel , on a narrow
bridge or on a narrow road)
• When parallel parking
• When there is a rut or hole in the
surface of the road
• When driving on a metal cover
(grating), such as those used for
drainage ditches
• When driving up or down a steep
slope
• If a sensor is hit by a large amount of water, such as when driving on
a flooded road
• When loaded on ships or trucks
• Moving type automatic car wash
• Lift type parking area or multi- story parking lot
• Underground parking area
• Structures on the ground (speed
bumps, cat’s eyes, etc.)
• Differences in height
• When moving straight ahead or
turning right
• Snow-melting pipes
• Devices for detecting vehicles,
such as traffic lig hts, devices for
detecting traffic congestion, or
devices for detecting empty
spaces in parking areas
• Railroad tracks
• H-shaped steel
• When there are vehicles on both sides, or there is a vehicle that
resembles this vehicle
●Weather
• If a sensor is covered with ice, snow, dirt, etc. (when cleared, the
system will return to normal)
• If heavy rain or water strikes a sensor
• When driving in inclement weather such as fog, snow or a sandstorm
• When strong winds are blowing
●Other sonic wave sources
• When vehicle horns, vehicle detectors, motorcycle engines, air
brakes of large vehicles, the clear-

3284-5. Using the driving support systems
ance sonar of other vehicles or
other devices which produce ultra-
sonic waves are near the vehicle
• If a sticker or an electronic compo- nent, such as a backlit license
plate (especially fluorescent type),
fog lights, fender pole or wireless
antenna is insta lled near a sensor
●Changes in the vehicle posture
• If the vehicle is significantly tilted
• If the front of the vehicle is raised or lowered due to the carried load
• If the orientation of a sensor has been changed due t o a collision or
other impact
■Situations in which the Parking
Support Brake function (static
objects) may not operate prop-
erly
In some situations, such as the fol-
lowing, this function may not oper-
ate properly.
●Weather
• When a sensor or the area around a sensor is extremely hot or cold
• When strong winds are blowing
• If a sensor is covered with ice, snow, dirt, etc. (when cleared, the
system will return to normal)
• If heavy rain or water strikes a
sensor
• When driving in inclement weather such as fog, snow or a sandstorm • A sensor is froz
en. (Thawing the
area will resolve this problem.)
●Vehicle surroundings
• When an object that cannot be detected is between the vehicle
and a detected object
• If an object such as a vehicle, motorcycle, bicycle or pedestrian
cuts in front of the vehicle or runs
out from the side of the vehicle
• The vehicle is approaching a tall
or curved curb.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The objects draw too close to the sensor.
●Other ultrasonic waves sources
• When vehicle horns, vehicle detectors, motorcycle engines, air
brakes of large vehicles, the clear-
ance sonar of ot her vehicles or
other devices which produce ultra-
sonic waves are near the vehicle
• If a sticker or an electronic compo- nent, such as a backlit license
plate (especially fluorescent type),
fog lights, fender pole or wireless
antenna is installed near a sensor
●Changes in the v ehicle posture
• If the vehicle is significantly tilted
• If the front of the v ehicle is raised
or lowered due to the carried load
• If the orientation of a sensor has
been changed due to a collision or
other impact
• When equipment that may
obstruct a sensor is installed, such
as a bumper protector (an addi-
tional trim strip, etc.), hitch-
mounted bicycle carrier, or snow
plow
• If the suspension has been modi-
fied or tires of a size other than
specified are installed
• If paint or a stic ker is applied to
the sensor

3354-5. Using the driving support systems
4
Driving■ECB (Electronically Con-
trolled Brake System)
The electronically controlled
system generates braking force
corresponding to the brake
operation
■ABS (Anti-lock Brake Sys-
tem)
Helps to prevent wheel lock
when the brakes are applied
suddenly, or if the brakes are
applied while driving on a slip-
pery road surface
■Brake assist
Generates an increased level of
braking force after the brake
pedal is depressed when the
system detects a panic stop sit-
uation
■VSC (Vehicle Stability Con-
trol)
Helps the driver to control skid-
ding when swerving suddenly or
turning on slippery road sur-
faces.
■Enhanced VSC (Enhanced
Vehicle Stability Control)
Provides cooperative control of
the ABS, TRAC, VSC and EPS.
Helps to maintain directional
stability when swerving on slip-
pery road surfaces by con-
trolling steering performance.
■Trailer Sway Control
Helps the driver to control trailer
sway by selectively applying
brake pressure for individual
wheels and reducing driving
torque when trailer sway is
detected.
■TRAC (Traction Control)
Helps to maintain drive power
and prevent the drive wheels
from spinning when starting the
vehicle or accelerating on slip-
pery roads
■Active Cornering Assist
(ACA)
Helps to prevent the vehicle
from drifting to the outer side by
performing inner wheel brake
control when attempting to
accelerate while turning
■Hill-start assist control
Helps to reduce the backward
Driving assist systems
To keep driving safety and
performance, the following
systems operate automati-
cally in response to various
driving situations. Be
aware, however, that these
systems are supplementary
and should not be relied
upon too heavily when oper-
ating the vehicle.
Summary of the driving
assist systems

3364-5. Using the driving support systems
movement of the vehicle when
starting on an uphill
■EPS (Electric Power Steer-
ing)
Employs an electric motor to
reduce the amount of effort
needed to turn the steering
wheel
■E-Four (Electronic On-
Demand AWD system)
(AWD models)
Automatically switches from
front wheel drive to all-wheel
drive (AWD) according to the
driving conditions, helping to
ensure reliable handling and
stability. Examples of condi-
tions where the system will
switch to AWD are when corner-
ing, going uphill, starting off or
accelerating, and when the road
surface is slippery due to snow,
rain, etc.
■The Secondary Collision
Brake
When the airbag sensor detects
a collision, the brakes and brake
lights are automatically con-
trolled to reduce the vehicle
speed and that helps reduce the
possibility of further damage
due to a secondary collision
■When the
TRAC/VSC/ABS/Trailer Sway
Control systems are operating
The slip indicator will flash while the
TRAC/VSC/ABS/Trai ler Sway Con-
trol systems are operating.
■Disabling the TRAC system
If the vehicle gets stuck in mud, dirt
or snow, the TRAC system may
reduce power from the hybrid sys-
tem 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 .
“Traction Control Turned Off” will be
shown on the multi-information dis-
play.
Press again to turn the system
back on.
■Turning off the
TRAC/VSC/Trailer Sway Con-
trol systems
To turn the TRAC/VSC/Trailer Sway
Control systems of f, 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
Turned Off” will be shown on the
multi-informat ion display.
*
Press again to turn the systems
back on.