wheel Lexus GS350 2018 Service Manual

GS350_300_GS F_OM_OM30G34U_(U)
2514-5. Using the driving support systems
4
Driving
◆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.

252
GS350_300_GS F_OM_OM30G34U_(U)4-5. Using the driving support systems
WARNING
■Before using LKA system
Do not rely solely upon the LKA system. Th
e 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.

GS350_300_GS F_OM_OM30G34U_(U)
2534-5. Using the driving support systems
4
Driving
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/GS300GS F
Indications on multi-information display
1
2

254
GS350_300_GS F_OM_OM30G34U_(U)4-5. Using the driving support systems
Lane departure alert function display
Displayed when the multi-information disp
lay 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 approximatel y 32 mph (50 km/h) or more.
• System recognizes white (yellow) lines.
• Width of traffic lane is approx imately 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. 257)
●Steering assist function
This function operates when all of the follo wing 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. 100, 108)
• Vehicle is not accelerated or dece lerated 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 (Pre-Collision System) are not operating.
• TRAC or VSC is not turned off.
• GS F: Hands off steering wheel alert is not displayed. ( →P. 255)
3
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 (ye
llow) lines or is
temporarily canceled.

GS350_300_GS F_OM_OM30G34U_(U)
2554-5. Using the driving support systems
4
Driving
●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. 100, 108)
• 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. 257)
●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. 100, 108)
• 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. 257)
• Vehicle does not accele rate 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 (Pre-Collision System) are not operating.
• TRAC or VSC is not turned off.
• GS F: Hands off steering wheel alert is not displayed. ( →P. 255)
• Steering assist function is not operating.
■Temporary cancellation of functions
When operation conditions are no longer met, a function may be temporarily canceled.
However, when the operation conditions are met again, operat ion of the function is auto-
matically restored. ( →P. 254)
■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.
■Hands off steering wheel alert
GS350/GS300: When the system determines that the driver has removed the hands
from the steering wheel while the steering as sist function or lane centering function is
operating, a warning message is displa yed on the multi-information display.
If the driver continues to keep the hands off of the steering wheel, a buzzer sounds, a
warning message is displayed. This alert also operates in the same way when the driver
continuously operates the steering wheel only a small amount. However, depending on
the road conditions, etc., the function may not cancel.

256
GS350_300_GS F_OM_OM30G34U_(U)4-5. Using the driving support systems
GS F: When the system determines that the driver has removed the hands from the
steering wheel while the steering assist function or lane centering function is operating, a
warning message is displayed on the multi-information display.
If the driver continues to keep the hands off of the steering wheel, a warning message is
displayed and the function is temporarily canc eled. This alert also operates in the same
way when the driver continuously operates the steering wheel only a small amount.
However, depending on the road conditions, etc., the function may not cancel.
■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.

GS350_300_GS F_OM_OM30G34U_(U)
2574-5. Using the driving support systems
4
Driving
■Warning message
Warning messages are used to indicate a system malfunction or to inform the driver of
the need for caution while driving. ( →P. 441)
■Customization
The following settings can be changed.
For how to change settings, refer to P. 545.
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_GS F_OM_OM30G34U_(U)
2694-5. Using the driving support systems
4
Driving
■Conditions under which the vehicle-to-vehicle distance control mode may not function
correctly
In the case of the following conditions, o perate the brake pedal (or accelerator pedal,
depending on the situ ation) as necessary.
As the sensor may not be able to correctly detect vehicles ahead, the system may not
operate properly.
●When the vehicle ahead of you decelerates suddenly
●Preceding vehicle has an extremely high
ground clearance
●When the road curves or when the lanes are
narrow
●When steering wheel operation or your posi-
tion in the lane is unstable

286
GS350_300_GS F_OM_OM30G34U_(U)4-5. Using the driving support systems
TVD (Torque Vectoring Differential) (GS F)
With the engine switch in IGNITION
ON mode, pressing the TVD switch
changes the TVD control mode.
The current TVD control mode will be
displayed on the meters.
STANDARD mode
This is the default mode and provides
an optimum balance of driving agility
and stability.
SLALOM mode
This mode emphasizes enhanced
steering response.
TRACK mode
This mode emphasiz
es stability for
high speed sporty driving.
The multi-information display shows the di stribution of driving force between the
right and left rear wheels. ( →P. 113)
The TVD system distributes driving force (torque) between the right an\
d left
rear wheels automatically. This syst em contributes to enhanced steering
response while cornering and increased traction when exiting a corner, pro-
viding an agile driving experience.
Changing TVD control modes
1
2
3
TVD control status on the multi-information display

288
GS350_300_GS F_OM_OM30G34U_(U)4-5. Using the driving support systems
Driving assist systems
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the br
akes are applied suddenly, or if the
brakes are applied while drivin g on a slippery road surface
◆Brake assist
Generates an increased level of br aking force after the brake pedal is
depressed when the system detects a panic stop situation
◆VSC (Vehicle Stability Control)
Helps the driver to contro l skidding when swerving suddenly or turning on
slippery road surfaces
◆Enhanced VSC (Enhanced Vehicle Stability Control)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road sur-
faces by controlling steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and pr event the drive wheels from spinning
when starting the vehicle or accelerating on slippery roads
◆Hill-start assist control
Helps to prevent the vehicle from ro lling backward when starting on an
incline.
To help enhance driving safety and perf ormance, the following systems oper-
ate automatically in response to variou s driving situations. Be aware, however,
that these systems are supplementary and should not be relied upon too heav-
ily when operating the vehicle.