
1704-5. Using the driving support systems
If either of the following occur while the pre-collision braking function is operating, it will be
canceled:
• The accelerator pedal is depressed strongly.
• The steering wheel is turned sharply or abruptly.
●Emergency steering assist
When the turn signal lights are flashing, emergency steering assist will not operate in case of
an emergency.
If any of the following occur while the emergency st eering assist function is operating, it will
be canceled:
• The accelerator pedal is depressed strongly.
• The steering wheel is turned sharply or abruptly.
• The brake pedal is depressed.
●Intersection right/left turn a ssistance (pre-collision warning)
When the turn signal lights are not flashing, support for turning left or right at an intersection
which targets oncoming vehicles does not work.
●Intersection right/left turn a ssistance (pre-collision braking)
Detectable objectsVehicle speedRelative speed between your
vehicle and object
Preceding and stopped vehi- clesApprox. 7 to 110 mph (10 to 180 km/h)Approx. 7 to 110 mph (10 to 180 km/h)
Oncoming vehiclesApprox. 7 to 110 mph (10 to 180 km/h)Approx. 13 to 110 mph (20 to 180 km/h)
Bicyclists and pedestriansApprox. 7 to 50 mph (10 to 80 km/h)Approx. 7 to 50 mph (10 to 80 km/h)
Detectable objectsVehicle speedRelative speed between your vehicle and object
Preceding and stopped vehi-cles, bicyclists and pedestri- ansApprox. 25 to 50 mph (40 to 80 km/h)Approx. 25 to 50 mph (40 to 80 km/h)
Detectable objectsVehicle speedOncoming vehicle speedRelative speed
between your vehi- cle and object
Oncoming vehiclesApprox. 7 to 15 mph (10 to 25 km/h)Approx. 20 to 35
mph (30 to 55 km/h)Approx. 25 to 50 mph (40 to 80 km/h)
PedestriansApprox. 7 to 15 mph (10 to 25 km/h)Approx. 7 to 15 mph (10 to 25 km/h)

1714-5. Using the driving support systems
4
Driving
When the turn signal lights are not flashing, support for turning left or right at an intersection
which targets oncoming vehicles does not work.
■Object detection function
The system detects ob jects based on their
size, profile, motion, etc. However, an object
may not be detected depending on the sur-
rounding brightness and the motion, pos-
ture, and angle of the detected object,
preventing the system from operating prop-
erly. ( P.172)
The illustration shows an image of detect-
able objects.
■Conditions under which the system may
operate even if there is no possibility of a
collision
●In some situations such as the following,
the system may determine that there is a
possibility of a frontal collision and oper-
ate.
• When passing a detectable object, etc.
• When changing lanes while overtaking a
detectable object, etc.
• When approaching a detectable object
in an adjacent lane or on the roadside,
such as when changing the course of
travel or driving on a winding road • When rapidly closing on a detectable
object, etc.
• When approaching objects on the road-
side, such as detectable objects, guard-
rails, utility poles, trees, or walls
• When there is a detectable object or
other object by th e roadside at the
entrance of a curve
• When there are patterns or paint in front of your vehicle that may be mistaken for a
detectable object
• When the front of your vehicle is hit by water, snow, dust, etc.
• When overtaking a detectable object
that is changing lanes or making a
right/left turn
Detectable objectsVehicle speedOncoming vehicle
speedRelative speed
between your vehi- cle and object
Oncoming vehiclesApprox. 10 to 15 mph (15 to 25 km/h)Approx. 20 to 28
mph (30 to 45 km/h)Approx. 28 to 43
mph (45 to 70 km/h)
PedestriansApprox. 7 to 15 mph (10 to 25 km/h)Approx. 7 to 15 mph (10 to 25 km/h)

1744-5. Using the driving support systems
as heavy rain, fog, snow or a sandstorm
• When driving through steam or smoke
• When the surrounding area is dim, such as at dawn or dusk, or while at night or in
a tunnel, making a detectable object
appear to be nearly the same color as its
surroundings
• When driving in a place where the sur- rounding brightness changes suddenly,
such as at the entrance or exit of a tunnel
• After the engine has started the vehicle has not been driven for a certain amount
of time
• While making a left/right turn and for a few seconds after making a left/right turn
• While driving on a curve and for a few seconds after driving on a curve
• If your vehicle is skidding
• If the front of the vehicle is raised or low-
ered
• If the wheels are misaligned
• If a wiper blade is blocking the front cam- era
• The vehicle is being driven at extremely high speeds
• When driving on a hill
• If the radar sensor or front camera is mis-
aligned
• When driving in a traffic lane separated
by more than one lane where oncoming
vehicles are driving while making a
right/left turn
• When largely out of place with the oppo- site facing targeted oncoming vehicle
during a right/left turn • While making a right/left turn, when a
pedestrian approaches from behind or
side of your vehicle
●In addition to the above, in some situa-
tions, such as the following, the emer-
gency steering assist may not operate.
• When the white (yellow) lane lines are difficult to see, such as when they are
faint, diverging/merging, or a shadow is
cast upon them
• When the lane is wider or narrower than
normal
• When there is a light and dark pattern on the road surface, such as due to road
repairs
• When the target is too close
• When there is insufficient safe or unob- structed space for the vehicle to be
steered into
• If oncoming vehicle is present
• If VSC function is operating
●In some situations su ch as the following,
sufficient braking forc e or steering force
may not be obtained, preventing the sys-
tem from performing properly:
• If the braking functions cannot operate to their full extent, such as when the brake
parts are extremely cold, extremely hot,
or wet
• If the vehicle is not properly maintained (brakes or tires are excessively worn,
improper tire inflation pressure, etc.)
• When the vehicle is being driven on a gravel road or other slippery surface
• When the road surface has deep wheel tracks
• When driving on a hill road
• When driving on a road that has inclines
to the left or right
■If VSC is disabled
●If VSC is disabled ( P.230), the
pre-collision brake assist and pre-colli-
sion braking functions are also disabled.

1754-5. Using the driving support systems
4
Driving
●The PCS warning light will turn on and
“VSC Turned OFF Pre-Collision Brake
System Unavailable” will be displayed on
the multi-information display.LTA (Lane Tracing Assist)
While driving on a road with clear
white (yellow) lane lines, the LTA
system warns the driver if the vehi-
cle may deviate from the current
lane or course
*, and also can
slightly operate the steering wheel
to help avoid deviation from the
lane or course
*. Also, while the
dynamic radar cruise control with
full-speed range ( P.187) is oper-
ating, this system will operate the
steering wheel to maintain the vehi-
cle’s lane position.
The LTA system recognizes white
(yellow) lane lines or a course
*
using the front camera. Addition-
ally, it detects preceding vehicles
using the front camera and radar.
*: Boundary between asphalt and the side of the road, such as grass, soil, or
a curb

1784-5. Using the driving support systems
■Lane departure alert function
When the system determines that the
vehicle might depart from its lane or
course
*, a warning is displayed on the
multi-information display, and either a
warning buzzer will sound or the steer-
ing wheel will vibrate to alert the driver.
When the warning buzzer sounds or the
steering wheel vibrates, check the area
around your vehicle and carefully operate
the steering wheel to move the vehicle
back to the cent er of the lane.
When the system determines that the vehi-
cle might depart from its lane and that the
possibility of a collision with an overtaking
vehicle in the adjacent lane is high, the lane
departure alert will operate even if the turn
signals are operating.
*: Boundary between asphalt and the side of the road, such as grass, soil, or a curb
WARNING
●Light from the headlights of an oncom-
ing vehicle, the sun, etc. enters the
camera.
●The vehicle is driven on a slope.
●The vehicle is driven on a road which
tilts left or right, or a winding road.
●The vehicle is driven on an unpaved or
rough road.
●The traffic lane is excessively narrow
or wide.
●The vehicle is extremely tilted due to
carrying heavy luggage or having
improper tire pressure.
●The distance to the preceding vehicle
is extremely short.
●The vehicle is moving up and down a
large amount due to road conditions
during driving (poor roads or road
seams).
●When driving in a tunnel or at night
with the headlights of f or when a head-
light is dim due to its lens being dirty or
it being misaligned.
●The vehicle is struck by a crosswind.
●The vehicle is affected by wind from a
vehicle driven in a nearby lane.
●The vehicle has just changed lanes or
crossed an intersection.
●Tires which differ by structure, manu-
facturer, brand or tread pattern are
used.
●When tires of a size other than speci-
fied are installed.
●Snow tires, etc. are equipped.
●The vehicle is being driven at
extremely high speeds.
Functions included in LTA system

1794-5. Using the driving support systems
4
Driving
■Steering assist function
When the system determines that the
vehicle might depart from its lane or
course
*, the system provides assis-
tance as necessary by operating the
steering wheel in small amounts for a
short period of time to keep the vehicle
in its lane.
When the system determines that the vehi-
cle might depart from its lane and that the
possibility of a collision with an overtaking
vehicle in the adjacent lane is high, the
steering assist function will operate even if
the turn signals are operating.
*: Boundary between asphalt and the side of the road, such as grass, soil, or a curb
■Vehicle sway warning function
When the vehicle is swaying within a
lane, the warning buzzer will sound and
a message will be displayed on the
multi-information display to alert the
driver.
■Lane centering function
This function is linked with dynamic
radar cruise control with full-speed
range and provides the required assis-
tance by operating the steering wheel
to keep the vehicle in its current lane.
When dynamic radar cruise control with
full-speed range is not operating, the lane
centering function does not operate.
In situations where the white (yellow) lane
lines are difficult to see or are not visible,
such as when in a traffic jam, this function
will operate to help follow a preceding
vehicle by monitoring the position of the
preceding vehicle.

1954-5. Using the driving support systems
4
Driving
●When the VSC or TRAC system is
turned off.
●The sensor cannot detect correctly
because it is covered in some way.
●When the brake control or output restric-
tion control of a driving support system
operates.
(For example: Pre-Collision System,
Drive-Start Control)
●The parking brake is operated.
●The vehicle is stopped by system control
on a steep incline.
●The following are detected when the
vehicle has been stopped by system con-
trol:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The vehicle has been stopped for about 3 minutes.
If vehicle-to-vehicle distance control mode
is automatically canceled for any reasons
other than the above, there may be a mal-
function in the system. Contact your Lexus
dealer.
■Automatic cancelation of constant
speed control mode
Constant speed control mode is automati-
cally canceled in the following situations:
●Actual vehicle speed is more than
approximately 10 mph (16 km/h) below
the set vehicle speed.
●Actual vehicle speed falls below approxi-
mately 20 mph (30 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is
turned off.
●When the brake control or output restric-
tion control of a driving support system
operates.
(For example: Pre-Collision System,
Drive-Start Control)
●The parking brake is operated.
If constant speed cont rol mode is automati-
cally canceled for any reasons other than
the above, there may be a malfunction in the
system. Contact your Lexus dealer.
■Situations in which the curve speed
reduction function may not operate
In situations such as the following, the curve
speed reduction function may not operate:
●When the vehicle is being driven around
a gentle curve
●When the accelerato r pedal is being
depressed
●When the vehicle is being driven around
an extremely short curve
■Brake operation
A brake operation sound may be heard and
the brake pedal response may change, but
these are not malfunctions.
■Warning messages and buzzers for
dynamic radar cruise control with
full-speed range
Warning messages and buzzers are used to
indicate a system malfunction or to inform
the driver of the need for caution while driv-
ing. If a warning messa ge is shown on the
multi-information display, read the message
and follow the instructions. ( P.163, 338)
■When the sensor may not be correctly
detecting the vehicle ahead
In the case of the fo llowing and depending
on the conditions, operate the brake pedal
when deceleration of the system is insuffi-
cient or operate the accelerator pedal
when acceleration is required.
As the sensor may not be able to correctly
detect these types of vehicles, the approach
warning ( P.192) may not be activated.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving in the same
lane
●Vehicles with small rear ends (trailers
with no load on board, etc.)

2054-5. Using the driving support systems
4
Driving
■The system can be operated when
●The engine switch is in IGNITION ON
mode.
●Intuitive parking assist function is on.
●The vehicle speed is less than about 6
mph (10 km/h).
●A shift lever other than P.
■Setting the buzzer volume
The buzzer volume can be adjusted on the
multi-information display. ( P.202)
■If “Parking Assist Unavailable Clean
Parking Assist Sensor” is displayed on
the multi-information display
A sensor may be covered with ice, snow,
dirt, etc. Remove the ice, snow, dirt, etc.,
from the sensor to return the system to nor-
mal.
Also, due to ice forming on a sensor at low
temperatures, a warning message may be
displayed or the sensor may not be able to detect an object. Once the ice melts, the
system will return to normal.
■If “Parking Assist Unavailable” is dis-
played on the multi-information display
●Water may be continuo
usly flowing over
the sensor surface, such as in a heavy
rain. When the system determines that it
is normal, the system will return to nor-
mal.
●Initialization may no t have been per-
formed after a battery terminal was dis-
connected and reconnect ed. Initialize the
system. ( P.205)
If this message contin ues to be displayed
even after initialization, have the vehicle
inspected by your Lexus dealer.
■If a battery terminal has been discon-
nected and reconnected
The system needs to be initialized. To initial-
ize the system, drive the vehicle straight
ahead for 5 seconds or more at a speed of
approximately 22 mph (35 km/h) or more.
■Sensor detection information
●The sensor's detection areas are limited
to the areas around the vehicle front and
rear bumpers.
●The following situations may occur
during use.
• Depending on the sh ape of the object
and other factors, the detection distance
may shorten, or detection may be impos-
sible.
• There will be a short delay between
object detection and di splay. Even at low
speeds, there is a possibility that the
object will come wi thin the sensor’s
detection areas befo re the display is
shown and the warning beep 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 buzzer if buzzers for other systems are sounding.
■Objects which the system may not be
properly detected
The shape of the object may prevent the
sensor from detecting it. Pay particular
attention to the following objects:
●Wires, fences, ropes, etc.
WARNING
■When to disable the function
In the following situations, disable the
function as it may operate even though
there is no possibility of a collision.
●Failing to observe the warnings above.
●A non-genuine Toyota suspension
(lowered suspension, etc.) is installed.
■Notes when washing the vehicle
Do not apply intensive bursts of water or
steam to the sensor area.
Doing so may result in the sensor mal-
functioning.
●When using a high pressure washer to
wash the vehicle, do not spray the sen-
sors directly, as doing so may cause a
sensor to malfunction.
●When using steam to clean the vehicle,
do not direct steam too close to the
sensors as doing so may cause a sen-
sor to malfunction.