Lexus GS350 (2020 year). Manual in english

257

iving

◆

Steering assist function

When the system determines that
the vehicle might depart from its
lane, the system provides assistance
as necessary by operating the steer-
ing wheel in small amounts for a
short period of time to keep the
vehicle in its lane.

GS350: If the system detects that

the steering 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 warning buzzer sounds.
GS F: If the system detects that the

steering wheel has not been oper-

ated 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 canceled.

◆

Vehicle sway warning function

When the vehicle is swaying or
appears as if it may depart from its
lane multiple times, the warning
buzzer sounds and a message is dis-
played on the multi-information dis-
play to alert the driver.

258

4-5. Using the driving support systems

◆

Lane centering function

This function is linked with radar
cruise control and provides the
required assistance by operating the
steering wheel to keep the vehicle in
its current lane.

When radar cruise control is not

operating, the lane centering func-

tion does not operate.
GS350: If the system detects that

the steering 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 warning buzzer sounds.
GS F: If the system detects that the

steering wheel has not been oper-

ated 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 canceled.

259

4-5. Using the driving support systems

iving

WARNING

■

Before using LKA system

Do not rely solely upon the LKA system. The LKA system does not automatically drive

the vehicle or reduce the amount of attention that must be paid to the area in front of

the vehicle. The driver must always assume full responsibility for driving safely by pay-

ing careful attention to the surrounding conditions and operating the steering wheel to

correct the path of the vehicle. Also, the driver must take adequate breaks when

fatigued, such as from driving for a long period of time.

Failure to perform appropriate driving operations and pay careful attention may lead to

an accident, resulting in death or serious injury.

■

To avoid operating LKA system by mistake

When not using the LKA system, use the LKA switch to turn the system off.

■

Situations unsuitable for LKA system

Do not use the LKA system in the following situations.

The system may not operate properly and lead to an accident, resulting in death or

serious injury.

●

A spare tire, tire chains, etc. are equipped.

●

When the tires have been excessively worn, or when the tire inflation pressure is low.

●

Tires which differ by structure, manufacturer, brand or tread pattern are used.

●

Objects or patterns that could be mistaken for white (yellow) lines are present on the

side of the road (guardrails, curbs, reflective poles, etc.).

●

Vehicle is driven on a snow-covered road.

●

White (yellow) lines are difficult to see due to rain, snow, fog, dust, etc.

●

Asphalt repair marks, white (yellow) line marks, etc. are present due to road repair.

●

Vehicle is driven in a temporary lane or restricted lane due to construction work.

●

Vehicle is driven on a road surface which is slippery due to rainy weather, fallen snow,

freezing, etc.

●

Vehicle is driven in traffic lanes other than on highways and freeways.

●

Vehicle is driven in a construction zone.

■

Preventing LKA system malfunctions and operations performed by mistake

●

Do not modify the headlights or place stickers, etc. on the surface of the lights.

●

Do not modify the suspension etc. If the suspension etc. needs to be replaced, con-

tact your Lexus dealer.

●

Do not install or place anything on the hood or grille. Also, do not install a grille guard

(bull bars, kangaroo bar, etc.).

●

If your windshield needs repairs, contact your Lexus dealer.

260

4-5. Using the driving support systems

Press the LKA switch to turn the LKA system on.

The LKA indicator illuminates and a message is displayed on the multi-information

display.
Press the LKA switch again to turn the LKA system off.
When the LKA system is turned on or off, operation of the LKA system continues in

the same condition the next time the engine is started.

LKA indicator
The illumination condition of the
indicator informs the driver of the
system operation status.

Illuminated in white:

LKA system is operating.
Illuminated in green:

Steering wheel assistance of the steer-

ing assist function or lane centering

function is operating.
Flashing in orange:

Lane departure alert function is operat-

ing.

Operation display of steering wheel
operation support
Indicates that steering wheel assistance of the steering assist function or lane
centering function is operating.

Turning LKA system on



GS350



GS F

Indications on multi-information display

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4-5. Using the driving support systems

iving

Lane departure alert function display
Displayed when the multi-information display is switched to the driving assist
system information screen.

■

Operation conditions of each function

●

Lane departure alert function
This function operates when all of the following conditions are met.
• LKA is turned on.

• Vehicle speed is approximately 32 mph (50 km/h) or more.

• System recognizes white (yellow) lines.

• Width of traffic lane is approximately 9.8 ft. (3 m) or more.

• Turn signal lever is not operated.

• Vehicle is driven on a straight road or around a gentle curve with a radius of more

than approximately 492 ft. (150 m).

• No system malfunctions are detected. (



P. 264)

●

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

of the multi-information display is set to “On”.

(



P. 106, 114)

• Vehicle is not accelerated or decelerated by a certain amount or more.

• Steering wheel is not operated with a steering force level suitable for changing

lanes.

• ABS, VSC, TRAC and PCS (Pre-Collision System) are not operating.

• TRAC or VSC is not turned off.

• GS F: Hands off steering wheel alert is not displayed. (



P. 263)



Inside of displayed white lines is
white



Inside of displayed white lines is
black

Indicates that the system is recognizing
white (yellow) lines. When the vehicle
departs from its lane, the white line dis-
played on the side the vehicle departs
from flashes orange.

Indicates that the system is not able to
recognize white (yellow) lines or is
temporarily canceled.

262

4-5. Using the driving support systems

●

Vehicle sway warning function
This function operates when all of the following conditions are met.

• Setting for “Sway Warning” in

of the multi-information display is set to “On”.

(



P. 106, 114)

• 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. (



P. 264)

●

Lane centering function
This function operates when all of the following conditions are met.
• LKA is turned on.

• Setting for “Steering Assist” and “Lane Center” in

of the multi-information

display are set to “On”. (



P. 106, 114)

• System recognizes white (yellow) lines.

• Dynamic radar cruise control with full-speed range is operating.

• Width of traffic lane is approximately 8.2 to 13.5 ft. (2.5 to 4.1 m).

• Turn signal lever is not operated.

• Vehicle is driven on a straight road or around a gentle curve with a radius of more

than approximately 656 ft. (200 m).

• No system malfunctions are detected. (



P. 264)

• Vehicle does not accelerate or decelerate by a certain amount or more.

• Steering wheel is not operated with a steering force level suitable for changing

lanes.

• ABS, VSC, TRAC and PCS (Pre-Collision System) are not operating.

• TRAC or VSC is not turned off.

• GS F: Hands off steering wheel alert is not displayed. (



P. 263)

• Steering assist function is not operating.

■

Temporary cancellation of functions

When the operation conditions are no longer met, a function may be temporarily can-

celed. However, when the operation conditions are met again, operation of the function

is automatically restored. (



P. 261)

■

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 operate at all.

■

Lane departure alert function

The warning buzzer may be difficult to hear due to external noise, audio playback, etc.

Also, it may be difficult to feel steering wheel vibrations due to the road conditions, etc.

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4-5. Using the driving support systems

iving

■

Hands off steering wheel warning

GS350:

Depending on the vehicle and road conditions, the warning may not operate.
GS F:

Depending on the vehicle and road conditions, the warning may not operate.

■

Vehicle sway warning function

Depending on the vehicle and road conditions, the warning may not operate.

When the system determines that the driver has

removed their hands from the steering wheel

while the steering assist function or lane center-

ing function is operating, 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 display.
If the driver continues to keep their hands off of

the steering wheel, a buzzer sounds and a warn-

ing message and the symbol shown in the illus-

tration are displayed on the multi-information

display. This warning also operates in the same

way when the driver continuously operates the

steering wheel only a small amount. Always

keep your hands on the steering wheel when

using this system, regardless of warnings.

When the system determines that the driver has

removed their hands from the steering wheel

while the steering assist function or lane center-

ing function is operating, 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 display.
If the driver continues to keep their hands off of

the steering wheel, a warning message and the

symbol shown in the illustration are displayed on

the multi-information display, and the function is

temporarily canceled. This warning also oper-

ates in the same way when the driver continu-

ously operates the steering wheel only a small

amount. Always keep your hands on the steer-

ing wheel when using this system, regardless of

warnings.

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

displayed on the multi-information display.

264

4-5. Using the driving support systems

■

White (yellow) lines are only on one side of road

The LKA system will not operate for the side on which white (yellow) lines could not be

recognized.

■

Conditions in which functions may not operate properly

In the following situations, the camera sensor may not detect white (yellow) lines and var-

ious functions may not operate normally.

●

There are shadows on the road that run parallel with, or cover, the white (yellow) lines.

●

The vehicle is driven in an area without white (yellow) lines, such as in front of a tollgate

or checkpoint, or at an intersection, etc.

●

The white (yellow) lines are cracked, “Botts’ dots”, “Raised pavement marker” or stones

are present.

●

The white (yellow) lines cannot be seen or are difficult to see due to sand, etc.

●

The vehicle is driven on a road surface that is wet due to rain, puddles, etc.

●

The traffic lines are yellow (which may be more difficult to recognize than lines that are

white).

●

The white (yellow) lines cross over a curb, etc.

●

The vehicle is driven on a bright surface, such as concrete.

●

The vehicle is driven on a surface that is bright due to reflected light, etc.

●

The vehicle is driven in an area where the brightness changes suddenly, such as at the

entrances and exits of tunnels, etc.

●

Light from the headlights of an oncoming vehicle, the sun, etc. enters the camera.

●

The vehicle is driven where the road diverges, merges, etc.

●

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 vehicle is driven around a sharp curve.

●

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 driv-

ing (poor roads or road seams).

●

The headlight lenses are dirty and emit a faint amount of light at night, or the beam axis

has deviated.

●

The vehicle is struck by a crosswind.

●

The vehicle has just changed lanes or crossed an intersection.

●

Snow tires, etc. are equipped.

■

Warning message

Warning messages are used to indicate a system malfunction or to inform the driver of

the need for caution while driving. (



P. 442)

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4-5. Using the driving support systems

iving

■

Customization

The following settings can be changed.

For how to change settings, refer to P. 542.

Function

Setting details

Lane departure alert function

Adjust alert sensitivity

Adjust alert type

Steering assist function

Turn steering wheel assistance on and off

Vehicle sway warning function

Turn function on and off

Adjust alert sensitivity

Lane centering function

Turn function on and off

266

4-5. Using the driving support systems

Dynamic radar cruise control



with full-speed

range



In vehicle-to-vehicle distance control mode, the vehicle automatically acceler-
ates, 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 control with full-speed range on freeways and
highways.

●

Vehicle-to-vehicle distance control mode (



P. 269)

●

Constant speed control mode (



P. 274)

Vehicle-to-vehicle distance switch
Display
Set speed
Indicators
Cruise control switch



: If equipped

Summary of functions



GS350



GS F

2
3
4
5

267

4-5. Using the driving support systems

iving

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 paying careful attention to your surroundings.

●

The dynamic radar cruise control with full-speed range provides driving assistance to

reduce the driver’s burden. However, there are limitations to the assistance provided.

Read the following conditions carefully. Do not overly rely on this system and always

drive carefully.
• When the sensor may not be correctly detecting the vehicle ahead: (



P. 276)

• Conditions under which the vehicle-to-vehicle distance control mode may not

function correctly: (



P. 277)

●

Set the speed appropriately depending on the speed limit, traffic flow, road condi-

tions, weather conditions, etc. The driver is responsible for checking the set speed.

●

Even when the system is functioning normally, the condition of the preceding 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 on this system or assuming the system ensures safety while

driving can lead to an accident, resulting in death or serious injury.

■

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 following distance

The dynamic radar cruise control with full-speed range is only intended to help the

driver in determining the following distance between the driver’s own vehicle and a

designated vehicle traveling ahead. It is not a mechanism that allows careless or inat-

tentive driving, and it is not a system that can assist the driver in low-visibility condi-

tions. It is still necessary for driver to pay close attention to the vehicle’s surroundings.

●

Assisting the driver to judge proper following distance

The dynamic radar cruise control with full-speed range determines whether the fol-

lowing 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 has limited capability to pre-

vent or avoid a collision with a vehicle traveling ahead. Therefore, if there is ever any

danger, the driver must take immediate and direct control of the vehicle and act

appropriately in order to ensure the safety of all involved.

268

4-5. Using the driving support systems

WARNING

■

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 following

situations.

Doing so may result in inappropriate speed control and could cause an accident result-

ing 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 covered 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.

●

At entrances to freeways and highways

●

When weather conditions are bad enough that they may prevent the sensors from

detecting correctly (fog, snow, sandstorm, heavy rain, etc.)

●

When there is rain, snow, etc. on the front surface of the radar sensor or camera sen-

sor

●

In traffic conditions that require frequent repeated acceleration and deceleration

●

During emergency towing

●

When an approach warning buzzer is heard often

269

4-5. Using the driving support systems

iving

This mode employs a radar sensor to detect the presence of vehicles up to
approximately 328 ft. (100 m) ahead, determines the current vehicle-to-vehicle
following distance, and operates to maintain a suitable following distance from
the vehicle ahead.

Note that vehicle-to-vehicle distance will close in when traveling on long downhill

slopes.

Example of constant speed cruising
When there are no vehicles ahead

The vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle dis-

tance can also be set by operating the vehicle-to-vehicle distance switch.

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 deceler-

ates 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

system control). After the vehicle ahead starts off, pushing the cruise control lever up

or depressing the accelerator pedal will resume follow-up cruising.

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 con-

stant speed cruising.

Driving in vehicle-to-vehicle distance control mode

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4-5. Using the driving support systems

Press the “ON/OFF” button to acti-
vate the cruise control.

Radar cruise control indicator will come

on and a message will be displayed on

the multi-information display.
Press the button again to deactivate the

cruise control.
If the “ON/OFF” button is pressed and

held for 1.5 seconds or more, the system

turns on in constant speed control

mode. (



P. 274)

Accelerate or decelerate, with
accelerator pedal operation, to the
desired vehicle speed (at or above
approximately 30 mph [50 km/h])
and push the lever down to set the
speed.

Cruise control “SET” indicator will come

on.
The vehicle speed at the moment the

lever is released becomes the set speed.
If the lever is operated while the vehicle speed is below approximately 30 mph

(50 km/h) and a preceding vehicle is present, the set speed will be adjusted to

approximately 30 mph (50 km/h).

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

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4-5. Using the driving support systems

iving

To change the set speed, operate the lever until the desired set speed is dis-
played.

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: Momentarily move
the lever in the desired direction.
Large adjustment: Hold the lever up or
down to change the speed, and release
when the desired speed is reached.
In the vehicle-to-vehicle distance control 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 (0.6mph)

each time the lever is

operated

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

or 1 km/h (0.6 mph)

increments for as long as the lever is held



For Canada, Guam and Puerto Rico
Fine adjustment: By 1 mph (1.6 km/h)

or 1 km/h (0.6mph)

each time the lever is

operated

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

or 5 km/h (3.1 mph)

increments for as long as the lever is held

In the constant speed control mode (



P. 274), the set speed will be increased or

decreased as follows:

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

or 1.6 km/h (1 mph)

each time the lever is

operated
Large adjustment: The speed will continue to change while the lever is held.

: When the set speed is shown in “MPH”

: When the set speed is shown in “km/h”

Adjusting the set speed

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4-5. Using the driving support systems

Pressing the switch changes the vehicle-to-vehicle distance as follows:

Long
Medium
Short

The vehicle-to-vehicle distance is set automatically to long mode when the engine

switch is turned to IGNITION ON mode.
If a vehicle is running ahead of you, the preceding vehicle mark will also be displayed.

Select a distance from the table below. Note that the distances shown corre-
spond to a vehicle speed of 50 mph (80 km/h). Vehicle-to-vehicle distance
increases/decreases in accordance with vehicle speed. When the vehicle is
stopped by system control, the vehicle stops at a certain vehicle-to-vehicle dis-
tance depending on the situation.

Changing the vehicle-to-vehicle distance (vehicle-to-vehicle distance
control mode)



GS350



GS F

Preceding
vehicle mark

Vehicle-to-vehicle distance settings (vehicle-to-vehicle distance con-
trol mode)

2
3

Distance options

Vehicle-to-vehicle distance

Long

Approximately 160 ft. (50 m)

Medium

Approximately 130 ft. (40 m)

Short

Approximately 100 ft. (30 m)

Lexus GS350 (2020 year). Manual in english - page 16