lane assist TOYOTA SIENNA HYBRID 2021 (in English) User Guide

2804-5. Using the driving support systems
■Lane centering function
This function is linked with
dynamic radar cruise control
with full-speed range and pro-
vides the required assistance by
operating the steering wheel to
keep the vehicle in its current
lane.
When dynamic radar cruise control
with full-speed range is not operat-
ing, the lane centering function
does not operate.
In situations where the white (yel-
low) lane lines are difficult to see or
are not visible, such as when in a
traffic jam, this fu nction will operate
to help follow a preceding vehicle
by monitoring the position of the
preceding vehicle.
If the system detects that the steer-
ing wheel has not been operated
for a fixed amount of time or the
steering wheel is not being firmly
gripped, a warning is displayed on the multi-information display and
the function is temporarily can-
celed.
Press the LTA switch to turn the
LTA system on.
The LTA indicator illuminates and a
message is display
ed on the multi-
information display.
Press the LTA switch again to
turn the LTA system off.
When the LTA syste m is turned on
or off, operation of the LTA system
continues in the same condition the
next time the hybrid system is
started.
Turning LTA system on

2814-5. Using the driving support systems
4
Driving
LTA indicator
The illumination condition of the
indicator informs the driver of the
system operation status.
Illuminated in white: LTA system is
operating.
Illuminated in green: Steering
wheel assistance of the steering
assist function or lane centering
function is operating.
Flashing in orange: Lane departure
alert function is operating.
Operation display of steering
wheel operation support
Displayed when the multi-informa-
tion display is switched to the driv-
ing support system information
display.
Indicates that steering wheel assis-
tance of the steering assist function or lane centering f
unction is operat-
ing.
Both outer sides of the lane are dis-
played: Indicates that steering
wheel assist of the lane centering
function is operating.
One outer side of the lane is dis-
played: Indicates that steering
wheel assist of the steering assist
function is operating.
Both outer sides of the lane are
flashing: Alerts the driver that their
input is necessary to stay in the
center of the lane (lane centering
function).
Follow-up cruising display
Displayed when the multi-informa-
tion display is swit ched to the driv-
ing support system information
display.
Indicates that steering assist of the
lane centering function is operating
by monitoring the position of a pre-
ceding vehicle.
When the follow-up cruising display
is displayed, if t he preceding vehi-
cle moves, your ve hicle may move
in the same way. Always pay care-
ful attention to your surroundings
and operate the steering wheel as
necessary to correct the path of the
vehicle and ensure safety.
Lane departure alert function
display
Displayed when the multi-informa-
tion display is swit ched to the driv-
ing support system information
display.
Indications on multi-infor-
mation display
A
B
C
D

2824-5. Using the driving support systems
Inside of displayed lines is
white
Indicates that the system is recog-
nizing white (yellow) lines or a
course
*. When the vehicle departs
from its lane, the white line dis-
played on the si de the vehicle
departs from flashes orange.
Inside of displayed lines is
black
Indicates that the system is not able
to recognize white (yellow) lines or
a course
* or is temporarily can-
celed.
*: Boundary between asphalt and the side of the road, such as
grass, soil, or a curb
■Operation conditions of each
function
●Lane departure alert function
This function oper ates when all of
the following cond itions are met. • LTA is turned on.
• Vehicle speed is approximately 32
mph (50 km/h) or more.
*1
• System recognizes white (yellow) lane lines or a course*2. (When a
white [yellow] line or course*2 is
recognized on only one side, the
system will operate only for the
recognized side.)
• Width of traffic lane is approxi-
mately 9.8 ft. (3 m) or more.
• Turn signal lever is not operated. (Vehicle with BSM: Except when
another vehicle is in the lane on
the side where the turn signal was
operated)
• Vehicle is not being driven around a sharp curve.
• No system malfunctions are
detected. ( P.285)
*1: The function oper ates even if the
vehicle speed is less than
approximately 32 mph (50 km/h)
when the lane centering function
is operating.
*2: Boundary between asphalt and the side of the road, such as
grass, soil, or a curb
●Steering assist function
This function operates when all of
the following conditions are met in
addition to the operation conditions
for the lane departure alert function.
• Setting for “Steering Assist” in the
screen of the multi-information
display is set to “ON”. ( P.104)
• Vehicle is not accelerated or decelerated by a fixed amount or
more.
• Steering wheel is not operated with a steering force level suitable
for changing lanes.
• ABS, VSC, TRAC and PCS are
not operating.
• TRAC or VSC is not turned off.
• Hands off steering wheel warning is not displayed. ( P.284)
●Vehicle sway warning function

2834-5. Using the driving support systems
4
Driving
This function operates when all of
the following cond itions are met.
• Setting for “Sway Warning” in the
screen of the mu lti-information
display is set to “ON”. ( P.104)
• Vehicle speed is approximately 32 mph (50 km/h) or more.
• Width of traffic lane is approxi- mately 9.8 ft. ( 3 m) or more.
• No system malfunctions are detected. ( P.285)
●Lane centering function
This function oper ates when all of
the following cond itions are met.
• LTA is turned on.
• Setting for “Steering Assist” and
“Lane Center” in the screen of
the multi-information display are
set to “ON”. ( P.104)
• This function recognizes white (yellow) lane lines or the position
of a preceding vehicle (except
when the preceding vehicle is
small, such as a motorcycle).
• The dynamic radar cruise control
with full-speed range is operating
in vehicle-to-vehic le distance con-
trol mode.
• Width of traffic lane is approxi-
mately 10 to 13 ft. (3 to 4 m).
• Turn signal lever is not operated.
• Vehicle is not being driven around a sharp curve.
• No system malfunctions are detected. ( P.285)
• Vehicle does not accelerate or decelerate by a fixed amount or
more.
• Steering wheel is not operated with a steering force level suitable
for changing lanes.
• ABS, VSC, TRAC and PCS are not operating.
• TRAC or VSC is not turned off.
• Hands off steering wheel warning
is not displayed. ( P.284)
• The vehicle is being driven in the
center of a lane.
• Steering assist function is not operating.
■Temporary cancelation of func-
tions
●When operation conditions are no
longer met, a function may be
temporarily canceled. However,
when the operation conditions are
met again, operation of the func-
tion is automatically restored.
( P.282)
●If the operation conditions
( P.282) are no longer met while
the lane centering function is
operating, the steering wheel may
vibrate and the buzzer may sound
to indicate that the function has
been temporarily canceled. How-
ever, if the “Steering wheel vibra-
tion” customization setting is set to
“On”, the system will notify the
driver by vibrating the steering
wheel instead of sounding the
buzzer.
■Steering assist function/lane
centering function
●Depending on the vehicle speed,
lane departure situation, road con-
ditions, etc., the driver may not
feel the function is operating or
the function may not operate at
all.
●The steering control of the func-
tion is overridden by the driver’s
steering wheel operation.
●Do not attempt to test the opera-
tion of the steering assist function.
■Lane departure alert function
●The warning buzzer may be diffi-
cult to hear due to external noise,
audio playback, etc. Also, it may
be difficult to fee l steering wheel
vibrations due to the road condi-
tions, etc.
●If the edge of the course* is not
clear or straight, the lane depar-
ture alert function may not oper-
ate.
●Vehicle with BSM: It may not be
possible for the system to deter-
mine if there is a danger of a colli-

2844-5. Using the driving support systems
sion with a vehicle in an adjacent
lane.
●Do not attempt to test the opera-
tion of the lane departure alert
function.
*: Boundary between asphalt and
the side of the road, such as
grass, soil, or a curb
■Hands off steering wheel warn-
ing
In the following situations, a warning
message urging the driver to hold
the steering wheel and the symbol
shown in the illustration are dis-
played on the multi-information dis-
play to warn the driver. The warning
stops when the sys tem determines
that the driver holds the steering
wheel. Always keep your hands on
the steering wheel when using this
system, regardless of warnings.
●When the system determines the
driver is not holding the steering
wheel while the lane centering
function is operating.
If the driver continues to keep their
hands off of the steering wheel, the
buzzer sounds, the driver is warned
and the function is temporarily can-
celed. This warning also operates in
the same way when the driver con-
tinuously operates the steering
wheel only a small amount.
The buzzer also sounds even if the
alert type is set to “Steering wheel
vibration”.
●When the system determines that
the vehicle may deviate from the
lane while driving around a curve while the lane centering function is
operating.
Depending on the vehicle condition
and road conditions, the warning
may not operate. Also, if the system
determines that the vehicle is driv-
ing around a curve, warnings will
occur earlier than during straight-
lane driving.
●When the system determines that
the driver is driving without hold-
ing the steering wheel while the
steering wheel assi st of the steer-
ing assist function is operating.
If the driver continues to keep their
hands off of the steering wheel and
the steering wheel assist is operat-
ing, the buzzer sounds and the
driver is warned. Each time the
buzzer sounds, the continuing time
of the buzzer becomes longer.
The buzzer also sounds even if the
alert type is set to “Steering wheel
vibration”.
■Vehicle sway warning function
When the system determines that
the vehicle is swaying while the
vehicle sway warning function is
operating, a buzzer sounds and a
warning message urging the driver
to rest and the sym bol shown in the
illustration are simultaneously dis-
played on the multi-information dis-
play.
Depending on the vehicle and road
conditions, the warning may not
operate.

2994-5. Using the driving support systems
4
Driving
●When steering wheel operation or
your position in the lane is unsta-
ble
●When the vehicle ahead of you
decelerates suddenly
●When driving on a road sur-
rounded by a structure, such as in
a tunnel or on a bridge
*: If equipped
BSM (Blind Spot Moni-
tor)*
The Blind Spot Monitor is a
system that has 2 functions:
The BSM (Blind Spot Moni-
tor) function
Assists the driver in making a
decision when changing lanes
 The RCTA (Rear Cross
Traffic Alert) function
Assists the driver when back-
ing up
These functions use the
same sensors.
WARNING
■Cautions regarding the use of
the BSM function
The driver is solely responsible for
safe driving. Always drive safely,
taking care to observe your sur-
roundings.
The BSM function is a supple-
mentary function which alerts the
driver that a vehicle is in a blind
spot of the outside rear view mir-
rors or is approaching rapidly from
behind into a blin d spot. Do not
overly rely on the BSM function.
As the function cannot judge if it is
safe to change lanes, over reli-
ance could lead to an accident
resulting in dea th or serious
injury.
As the system may not function
correctly under certain condi-
tions, the driver’s own visual con-
firmation of safety is necessary.

3054-5. Using the driving support systems
4
Driving
when driving on the edge of a
lane, and the vehicle in an adja-
cent lane is far away from your
vehicle
• When an accessory (such as a hitch-mounted bicycle carrier) is
installed to the r ear of the vehicle
• When the vehicle is heavily loaded in the luggage compart-
ment
• When there is a significant differ- ence in height between your vehi-
cle and the vehicle that enters the
detection area
• Immediately after the BSM func-
tion/RCTA function are turned on
• When towing a trailer
●Instances of the BSM function
unnecessarily detecting a vehicle
and/or object may increase in the
following situations:
• When the sensor is misaligned
due to a strong impact to the sen-
sor or its surrounding area
• When the distanc e between your
vehicle and a guar drail, wall, etc.
that enters the detection area is
short
• When driving up and down con-
secutive steep inclines, such as
hills, dips in the road, etc.
• When vehicle lanes are narrow, or
when driving on the edge of a
lane, and a vehicle traveling in a
lane other than the adjacent lanes
enters the detection area
• When driving on roads with sharp bends, consecutive curves, or
uneven surfaces
• When the tires are slipping or spinning
• When the distanc e between your
vehicle and a following vehicle is
short
• When an accessory (such as a hitch-mounted bicycle carrier) is
installed to the r ear of the vehicle
• When the vehicle throws up water
or snow behind.
■Operation of the RCTA
function
The RCTA function uses radar
sensors to detect vehicles
approaching from the right or left
at the rear of the vehicle and
alerts the driver of the presence
of such vehicles by flashing the
outside rear view mirror indica-
tors and sounding a buzzer.
Approaching vehicles
Detection areas
■RCTA icon display (if
equipped)
When a vehicle approaching
from the right or left at the rear
of the vehicle is detected, the
following will be displayed on
the audio system screen.
 When the Toyota parking
assist monitor (if equipped) is
displayed
The Rear Cross Traffic
Alert function (if
equipped)
A
B

3394-5. Using the driving support systems
4
Driving
WARNING
■The ABS does not operate
effectively when
●The limits of tire gripping perfor-
mance 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 normal conditions
The ABS is not designed to
shorten the vehicle’s stopping dis-
tance. Always maintain a safe dis-
tance from the vehicle in front of
you, especially in the following sit-
uations:
●When driving on d irt, 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
■TRAC/VSC may not operate
effectively when
Directional control and power may
not be achievable while driving on
slippery road surfaces, even if the
TRAC/VSC system is operating.
Drive the vehicle carefully in con-
ditions where stability and power
may be lost.
■Active Cornering Assist does
not operate effectively when
●Do not overly rely on Active
Cornering Assist. Active Corner-
ing Assist may not operate
effectively when accelerating
down slopes or driving on slip-
pery road surfaces.
●When Active Corn ering Assist
frequently operates, Active Cor-
nering Assist may temporarily
stop operating to ensure proper
operation of the brakes, TRAC
and VSC.
■Hill-start assist control does
not operate effectively when
●Do not overly rely on hill-start
assist control. Hill-start assist
control may not operate effec-
tively on steep inclines and
roads covered with ice.
●Unlike the parking brake, hill-
start assist control is not
intended to hold the vehicle sta-
tionary 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 acci-
dent.
■When the
TRAC/ABS/VSC/Trailer Sway
Control is activated
The slip indicator flashes. Always
drive carefully. Reckless driving
may cause an accident. Exercise
particular care when the indicator
light flashes.
■When the TRAC/VSC/Trailer
Sway Control systems are
turned off
Be especially careful and drive at
a speed appropriate to the road
conditions. As these are the sys-
tems to help ensure vehicle stabil-
ity and driving force, do not turn
the TRAC/VSC/Tra iler Sway Con-
trol systems off unless necessary.
Trailer Sway Control is part of the
VSC system and will not operate
if VSC is turned off or experiences
a malfunction.

3434-6. Driving tips
4
Driving
Use fluids that are appropriate
to the prevailing outside tem-
peratures.
• Engine oil
• Engine coolant
• Power control unit coolant
• Washer fluid
Have a service technician
inspect the condition of the
12-volt 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.
*: Tire chains cannot be mounted
on vehicles with 20-inch tires.
Winter driving tips
Carry out the necessary
preparations and inspec-
tions before driving the
vehicle in winter. Always
drive the vehicle in a man-
ner appropriate to the pre-
vailing weather conditions.
Pre-winter preparations
WARNING
■Driving with snow tires
Observe the following precautions
to reduce the risk of accidents.
Failure to do so may result in a
loss of vehicle control and cause
death or serious injury.
●Use tires of the specified size.
●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.
■Driving with tire chains (vehi-
cles with 17-inch or 18-inch
tires)
Observe the following precautions
to reduce the risk of accidents.
Failure to do so may result in the
vehicle being unable to be driven
safely, and may cause death or
serious injury.
●Do not drive in excess of the
speed limit specifi ed for the tire
chains being used, or 30 mph
(50 km/h), whichever is lower.
●Avoid driving on bumpy road
surfaces or over potholes.
●Avoid sudden acceleration,
abrupt steering, sudden brak-
ing and shifting operations that
cause sudden engine braking.
●Slow down sufficiently before
entering a curve to ensure that
vehicle control is maintained.
●Do not use LTA (Lane Tracing
Assist) system.

4697-2. Steps to take in an emergency
7
When trouble arises
■PCS warning light (warning buzzer)
■LTA indicator (warning buzzer)
■Intuitive parking assist OFF indicator (warning buzzer)
Warning lightDetails/Actions
(Flashes or illumi-
nates)
When a buzzer sounds simultaneously:
Indicates a malfunction has occurred in the PCS (Pre-
Collision System).
 Have the vehicle insp ected by your Toyota
dealer immediately.
When a buzzer does not sound:
The PCS (Pre-Collision System) has become tempo-
rarily unavailable, correctiv e action may be necessary.
 Follow the instructions d isplayed on the multi-
information display. ( P.265, 480)
If the PCS (Pre-Collision S ystem) or VSC (Vehicle Sta-
bility Control) syst em is disabled, the PCS warning
light will illuminate.
 P.274
Warning lightDetails/Actions
(Orange)
Indicates a malfunction in the LTA (Lane Tracing
Assist)
Follow the instructions d isplayed on the multi-
information display. ( P.285)
Warning lightDetails/Actions
(If equipped)
When a buzzer sounds:
Indicates a malfunction in t he Intuitive parking assist
function
 Have the vehicle insp ected by your Toyota
dealer immediately.
When a buzzer does not sound:
Indicates that the system i s temporarily unavailable,
possibly due to a sensor bei ng dirty or covered with
ice, etc.
 Follow the instructions d isplayed on the multi-
information display. ( P.311, 477)