Lexus ES250 (2023 year). Manual in english - page 11

: The function operates even if the vehicle

speed is less than approximately 32 mph
(50 km/h) when the lane centering
function is operating.

: 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 fol-
lowing conditions are met in addition to the
operation conditions for the lane departure
alert function.
• Vehicle is not accelerated or decelerated

by a fixed amount or more.

190

4-5. Using the driving support systems

• 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.

●

Vehicle sway warning function

This function operates when all of the fol-
lowing conditions are met.
• Setting for “Warning” in

of the multi-

information display is set to “On”.
(

• Vehicle speed is approximately 32 mph

(50 km/h) or more.

• Width of traffic lane is approximately 9.8

ft. (3 m) or more.

• No system malfunctions are detected.

(

●

Lane centering function

This function operates when all of the fol-
lowing conditions are met.
• LTA is turned on.
• Setting for “Lane Center” in

of the

multi-information display is set to “On”.
(

• This function recognizes white (yellow)

lane lines or the position of a preceding

vehicle (except when the preceding vehi-

cle is small, such as a motorcycle).

• The dynamic radar cruise control with

full-speed range is operating in vehicle-

to-vehicle distance control mode.

• Width of traffic lane is approximately 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.

(

• Vehicle does not accelerate or deceler-

ate 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. (



• The vehicle is being driven in the center

of a lane.

• Steering assist function is not operating.

■

Temporary cancelation of functions

●

When operation conditions are no lon-

ger met, a function may be temporarily

canceled. However, when the operation

conditions are met again, operation of

the function is automatically restored.

(



P.189)

●

If the operation conditions (



P.189) 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 tem-
porarily canceled. However, if the “Alert”
customization setting is set to

, 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 conditions, etc.,

the driver may not feel the function is

operating or the function may not oper-

ate at all.

●

The steering control of the function is

overridden by the driver’s steering wheel

operation.

●

Do not attempt to test the operation of

the steering assist function.

■

Lane departure alert function

●

The warning buzzer may be difficult to

hear due to external noise, audio play-

back, etc. Also, it may be difficult to feel

steering wheel vibrations due to the road

conditions, etc.

●

If the edge of the course

is not clear or

straight, the lane departure alert function

may not operate.

●

It may not be possible for the system to

determine if there is a danger of a colli-

sion with a vehicle in an adjacent lane.

●

Do not attempt to test the operation of

the lane departure alert function.

191

4-5. Using the driving support systems

Driving

: Boundary between asphalt and the side

of the road, such as grass, soil, or a curb

■

Hands off steering wheel warning

In the following situations, a warning mes-

sage urging the driver to hold the steering

wheel and the symbol shown in the illustra-

tion are displayed on the multi-information

display to warn the driver. The warning

stops when the system determines that the

driver holds the steering wheel. Always

keep your hands on the steering wheel

when using this system, regardless of warn-

ings.

●

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 tem-
porarily canceled. This warning also oper-
ates in the same way when the driver
continuously operates the steering wheel
only a small amount.
The buzzer also sounds even if the alert
type is set to

●

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 oper-
ate.

●

When the system determines that the

driver is driving without holding the steer-

ing wheel while the steering wheel assist

of the steering assist function is operat-

ing.

If the driver continues to keep their hands

off of the steering wheel and the steering
wheel assist is operating, 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

■

Vehicle sway warning function

When the system determines that the vehi-

cle is swaying while the vehicle sway warn-

ing function is operating, a buzzer sounds

and a warning message urging the driver to

rest and the symbol shown in the illustration

are simultaneously displayed on the multi-

information display.

Depending on the vehicle and road condi-

tions, the warning may not operate.

■

Warning message

If the following warning message is dis-

played on the multi-information display and

the LTA indicator illuminates in orange, fol-

low the appropriate troubleshooting proce-

dure. Also, if a different warning message is

displayed, follow the instructions displayed

on the screen.

●

“LTA Malfunction Visit Your Dealer”

The system may not be operating properly.
Have the vehicle inspected by your Lexus
dealer.

●

“LTA Unavailable”

The system is temporarily canceled due to a
malfunction in a sensor other than the front
camera. Turn the LTA system off, wait for a
little while, and then turn the LTA system
back on.

●

“LTA Unavailable at Current Speed”

192

4-5. Using the driving support systems

The function cannot be used as the vehicle
speed exceeds the LTA operation range.
Drive slower.

■

Customization

Function settings can be changed.
(Customizable features:

P.404)

: If equipped

When the front camera recognizes a
sign and/or information of a sign is

RSA (Road Sign Assist)

The RSA system recognizes spe-
cific road signs using the front cam-
era and/or navigation system
(when speed limit information is
available) to provide information to
the driver via the display.

If the system judges that the vehicle
is being driven over the speed limit,
performing prohibited actions, etc.
according to the recognized road
signs, it notifies the driver through a
visual notification and notification
buzzer.

WARNING

■

Before using the RSA

Do not rely solely upon the RSA system.

RSA is a system which supports the

driver by providing information, but it is

not a replacement for a driver’s own

vision and awareness. Drive safely by

always paying careful attention to the

traffic rules.

Indication on the multi-informa-
tion display

193

4-5. Using the driving support systems

Driving

available from the navigation system,
the sign will be displayed on the multi-
information display.



When the driving support system
information is selected, a maximum
of 3 signs can be displayed.
(





When a tab other than the driving
support system information is
selected, the following types of road
signs will be displayed. (



• Speed limit sign
• Do Not Enter sign (when notification is

necessary)

If signs other than speed limit signs are rec-
ognized, they will be displayed in an over-
lapping stack under the current speed limit
sign.

The following types of road signs,

including electronic signs and blinking
signs, are recognized.

A non-official or a recently introduced traf-
fic sign may not be recognized.

: Speed limit

: Do Not Enter

: Stop

: Yield

In the following situations, the RSA sys-
tem will notify the driver.



When the vehicle speed exceeds
the speed notification threshold of
the speed limit sign displayed, the
sign display will be emphasized and
a buzzer will sound.



When the RSA system recognizes a
do not enter sign and determines
that your vehicle has entered a no-
entry area, the displayed sign will
flash and a buzzer will sound.

Depending on the situation, a notifica-
tion function may not operate properly.

■

Setting procedure

Press

of the meter control

switches and select

Supported types of road signs

Notification function

194

4-5. Using the driving support systems

Press

of the meter control

switches and select “Vehicle Settings”,
then press “OK”

Press

of the meter control

switches and select

, then press

“OK”

Press

of the meter control

switches and select “RSA”, then press
“OK”

■

Automatic turn-off of RSA sign display

In the following situations, a displayed

speed limit sign and/or do not enter sign

will stop being displayed automatically:

●

No sign has been recognized for a cer-

tain distance.

●

The road changes due to a left or right

turn, etc.

In the following situations, stop and yield

signs will stop being displayed automati-

cally:

●

The system determines that your vehicle

has passed the sign.

●

The road changes due to a left or right

turn, etc.

■

Conditions in which the function may

not operate or detect correctly

In the following situations, RSA does not

operate normally and may not recognize

signs, display the incorrect sign, etc. How-

ever, this does not indicate a malfunction.

●

The front camera is misaligned due to a

strong impact being applied to the sen-

sor, etc.

●

Dirt, snow, stickers, etc. are on the wind-

shield near the front camera.

●

In inclement weather such as heavy rain,

fog, snow or sand storms.

●

Light from an oncoming vehicle, the sun,

etc. enters the front camera.

●

The sign is dirty, faded, tilted or bent.

●

The contrast of electronic sign is low.

●

All or part of the sign is hidden by the

leaves of a tree, a pole, etc.

●

The sign is only visible to the front camera

for a short amount of time.

●

The driving scene (turning, lane change,

etc.) is judged incorrectly.

●

If a sign not appropriate for the currently

traveled lane, but the sign exists directly

after a freeway branches, or in an adja-

cent lane just before merging.

●

Stickers are attached to the rear of the

preceding vehicle.

●

A sign resembling a system compatible

sign is recognized.

●

Side road speed signs may be detected

and displayed (if positioned in sight of the

front camera) while the vehicle is travel-

ing on the main road.

●

Roundabout exit road speed signs may

be detected and displayed (if positioned

in sight of the front camera) while travel-

ing on a roundabout.

●

The front of the vehicle is raised or low-

ered due to the carried load.

●

The surrounding brightness is not suffi-

cient or changes suddenly.

●

When a sign intended for trucks, etc. is

recognized.

●

The navigation system map data is out-

dated.

●

The navigation system is not operating.

●

The speed information displayed on the

meter and on the navigation system may

be different due to the navigation system

using map data.

■

Speed limit sign display

If the engine switch was last turned off while

a speed limit sign was displayed on the

multi-information display, the same sign dis-

plays again when the engine switch is

turned to IGNITION ON mode.

■

If “RSA Malfunction Visit Your Dealer”

is shown

The system may be malfunctioning. Have

the vehicle inspected by your Lexus dealer.

■

Customization

Some functions can be customized. (Cus-

tomizable features:



P.404)

195

4-5. Using the driving support systems

Driving

■

Meter display

Multi-information display

Set speed

Indicators

■

Operation switches

Vehicle-to-vehicle distance switch

“+RES” switch

Cruise control main switch

Cancel switch

“-SET” switch

Dynamic radar cruise con-
trol with full-speed range

In vehicle-to-vehicle distance con-
trol mode, the vehicle automati-
cally accelerates, decelerates and
stops to match the speed changes
of the preceding vehicle even if the
accelerator pedal is not depressed.
In constant speed control mode,
the vehicle runs at a fixed speed.
Use the dynamic radar cruise con-
trol with full-speed range on free-
ways and highways.



Vehicle-to-vehicle distance con-
trol mode (



P.197)



Constant speed control mode
(

P.202)

System Components

WARNING

■

Before using dynamic radar cruise

control with full-speed range

●

Driving safely is the sole responsibility

of the driver. Do not rely solely on the

system, and drive safely by always pay-

ing careful attention to your surround-

ings.

●

The dynamic radar cruise control with

full-speed range provides driving

assistance to reduce the driver’s bur-

den. However, there are limitations to

the assistance provided.

Read the following conditions care-

fully. Do not overly rely on this system

and always drive carefully.

• When the sensor may not be correctly

detecting the vehicle ahead



P.204

• Conditions under which the vehicle-

to-vehicle distance control mode may

not function correctly

P.204

●

Set the speed appropriately depend-

ing on the speed limit, traffic flow, road

conditions, weather conditions, etc.

The driver is responsible for checking

the set speed.

196

4-5. Using the driving support systems

WARNING

●

Even when the system is functioning

normally, the condition of the preced-

ing vehicle as detected by the system

may differ from the condition

observed by the driver. Therefore, the

driver must always remain alert, assess

the danger of each situation and drive

safely. Relying solely on this system or

assuming the system ensures safety

while driving can lead to an accident,

resulting in death or serious injury.

●

Switch the dynamic radar cruise con-

trol with full-speed range setting to off,

using the cruise control main switch

when not in use.

■

Cautions regarding the driving assist

systems

Observe the following precautions, as

there are limitations to the assistance

provided by the system.

Failure to do so may cause an accident

resulting in death or serious injury.

●

Assisting the driver to measure follow-

ing distance

The dynamic radar cruise control with

full-speed range is only intended to

help the driver in determining the fol-

lowing distance between the driver’s

own vehicle and a designated vehicle

traveling ahead. It is not a mechanism

that allows careless or inattentive driv-

ing, 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 sur-

roundings.

●

Assisting the driver to judge proper

following distance

The dynamic radar cruise control with

full-speed range determines whether

the following distance between the

driver’s own vehicle and a designated

vehicle traveling ahead is within a set

range. 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 with

full-speed range does not include

functions which will prevent or avoid

collisions with vehicles ahead of your

vehicle. Therefore, if there is ever any

possibility of danger, the driver must

take immediate and direct control of

the vehicle and act appropriately in

order to ensure the safety of all

involved.

■

Situations unsuitable for dynamic

radar cruise control with full-speed

range

Do not use dynamic radar cruise control

with full-speed range in any of the follow-

ing situations.

Doing so may result in inappropriate

speed control and could cause an acci-

dent resulting in death or serious injury.

●

Roads where there are pedestrians,

cyclists, etc.

●

In heavy traffic

●

On roads with sharp bends

●

On winding roads

●

On slippery roads, such as those cov-

ered with rain, ice or snow

●

On steep downhills, or where there

are sudden changes between sharp up

and down gradients

Vehicle speed may exceed the set

speed when driving down a steep hill.

197

4-5. Using the driving support systems

Driving

This mode employs a radar to detect the presence of vehicles up to approximately
328 ft. (100 m) ahead, determines the current vehicle-to-vehicle following dis-
tance, and operates to maintain a suitable following distance from the vehicle
ahead. The desired vehicle-to-vehicle distance can also be set by operating the
vehicle-to-vehicle distance switch.

When driving on downhill slopes, the vehicle-to-vehicle distance may become shorter.

Example of constant speed cruising
When there are no vehicles ahead

WARNING

●

At entrances to freeways and high-

ways

●

When weather conditions are bad

enough that they may prevent the sen-

sors from detecting correctly (fog,

snow, sandstorm, heavy rain, etc.)

●

When there is rain, snow, etc. on the

front surface of the radar or front cam-

era

●

In traffic conditions that require fre-

quent repeated acceleration and

deceleration

●

During emergency towing

●

When an approach warning buzzer is

heard often

Driving in vehicle-to-vehicle distance control mode

198

4-5. Using the driving support systems

The vehicle travels at the speed set by the driver.

Example of deceleration cruising and follow-up cruising
When a preceding vehicle driving slower than the set speed appears

When a vehicle is detected running ahead of you, the system automatically decelerates
your vehicle. When a greater reduction in vehicle speed is necessary, the system applies
the brakes (the stop lights will come on at this time). The system will respond to changes in
the speed of the vehicle ahead in order to maintain the vehicle-to-vehicle distance set by
the driver. Approach warning warns you when the system cannot decelerate sufficiently to
prevent your vehicle from closing in on the vehicle ahead.
When the vehicle ahead of you stops, your vehicle will also stop (vehicle is stopped by sys-
tem control). After 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 operated and your vehicle moves to an overtaking lane while
driving at 50 mph (80 km/h) or more, the vehicle will accelerate to help to overtake a
passing vehicle.
The system’s identification of what is an overtaking lane may be determined solely based on
the location of the steering wheel in the vehicle (left side driver position versus right side
driver position.) If the vehicle is driven to a region where the overtaking lane is on a differ-
ent side from where the vehicle is normally driven, the vehicle may accelerate when the
turn signal lever is operated in the opposite direction to the overtaking lane (e.g., if the
driver normally operates the vehicle in a region where the overtaking lane is to the right but
then drives to a region where the overtaking lane 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 constant
speed cruising.

Press the cruise control main
switch to activate the cruise con-
trol.

Dynamic radar cruise control indicator will

come on and a message will be displayed

on the multi-information display. Press the

switch again to deactivate the cruise con-

trol.

If the cruise control main switch is pressed

and held for 1.5 seconds or more, the sys-

tem turns on in constant speed control

mode. (



P.202)

Setting the vehicle speed (vehi-
cle-to-vehicle distance control
mode)

199

4-5. Using the driving support systems

Driving

Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or above
approximately 20 mph [30 km/h])
and press the “-SET” switch to set
the speed.

Cruise control “SET” indicator will come

on.
The vehicle speed at the moment the

switch is released becomes the set speed.



Adjusting the set speed by the
switch

To change the set speed, press the
“+RES” or “-SET” switch until the
desired set speed is displayed.

Increases the speed

(Except when the vehicle has been
stopped by system control in vehicle-to-
vehicle distance control mode)

Decreases the speed

Fine adjustment: Press the switch.
Large adjustment: Press and hold the
switch to change the speed, and
release when the desired speed is
reached.
In the vehicle-to-vehicle distance con-
trol mode, the set speed will be
increased or decreased as follows:



For the U.S. mainland and Hawaii

Fine adjustment: By 1 mph (1.6 km/h)

or 1

km/h (0.6 mph)

each time the switch is

pressed
Large adjustment: Increases or decreases
in 1mph (1.6 km/h)

or 1 km/h (0.6 mph)

increments for as long as the switch is held



Except for the U.S. mainland and
Hawaii

Fine adjustment: By 1 mph (1.6 km/h)

or 1

km/h (0.6 mph)

each time the switch is

pressed
Large adjustment: Increases or decreases
in 5 mph (8 km/h)

or 5 km/h (3.1 mph)

increments for as long as the switch is held

In the constant speed control mode
(