warning Lexus GS350 2019 Owner's Manual

GS350_300_OM_OM30G96U_(U)
2574-5. Using the driving support systems
4
Driving
◆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/GS300: 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 dis-
played on the multi-information dis-
play 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.

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GS350_300_OM_OM30G96U_(U)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/GS300: 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 dis-
played on the multi-information dis-
play 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.

GS350_300_OM_OM30G96U_(U)
2594-5. Using the driving support systems
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Driving
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 cond itions 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 operat ions 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, cu rbs, 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 ot her than on highways and freeways.
●Vehicle is driven in a construction zone.
■Preventing LKA system malfunctions and operations perf ormed 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 repair s, contact your Lexus dealer.

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GS350_300_OM_OM30G96U_(U)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 approximatel y 32 mph (50 km/h) or more.
• Width of traffic lane is approx imately 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 accelera te 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 conditio ns are met again, operation of the function
is automatically restored. ( P. 261)
■Steering assist function/lane centering function
Depending on the vehicle speed, lane depart ure 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 f eel steering wheel vibrations due to the road conditions, etc.

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Driving
■Hands off steering wheel warning
GS350/GS300:
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 al so operates in the same
way when the driver cont inuously 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 th is 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.

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GS350_300_OM_OM30G96U_(U)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 ar ea 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 carry ing 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 am ount 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 lane s or crossed an intersection.
●Snow tires, etc. are equipped.
■Warning message
Warning messages are used to indicate a syst em malfunction or to inform the driver of
the need for caution while driving. ( P. 444)

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Driving
■Customization
The following settings can be changed.
For how to change settings, refer to P. 549.
FunctionSetting details
Lane departure alert functionAdjust alert sensitivity
Adjust alert type
Steering assist functionTurn steering wheel assistance on and off
Vehicle sway warning functionTurn function on and off
Adjust alert sensitivity
Lane centering functionTurn function on and off

GS350_300_OM_OM30G96U_(U)
2674-5. Using the driving support systems
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Driving
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 ca reful 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 norma lly, 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 distan ce between the driver’s own vehicle and a
designated vehicle traveling ahead. It is no t 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 pa y 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 trave ling 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.

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GS350_300_OM_OM30G96U_(U)4-5. Using the driving support systems
WARNING
■Situations unsuitable for dynamic rada
r 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 pede strians, cyclists, etc.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as thos e 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 fron t surface of the radar sensor or camera sen-
sor
●In traffic conditions that require frequent repeated a cceleration and deceleration
●During emergency towing
●When an approach warning buzzer is heard often

GS350_300_OM_OM30G96U_(U)
2694-5. Using the driving support systems
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Driving
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 main tain 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 sufficie ntly 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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