Lexus GS300h 2015 Owner's Manual

2914-5. Using the driving support systems
4
Driving
GS450h_300h_OM_OM30F00E_(EE)
◆Steering control 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.
Except for Israel: 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 function is temporarily
canceled.
For Israel: 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.
◆Ve h i c l e s w a y w a r n i n g
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.

2924-5. Using the driving support systems
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WA R N I N G
■Before using LDA system
Do not rely solely upon the LDA system. LDA is not a system which automatically
drives the vehicle or reduces 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 always paying careful attention to the surrounding conditions and operate the steer-
ing wheel to correct the path of the vehicle. Also, make sure to 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 LDA by mistake
When not using the LDA system, use the LDA switch to turn the system off.
■Situations unsuitable for LDA
Do not use the LDA 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 ma rks, 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.
●Vehicle is towing a trailer or another vehicle.
■Preventing LDA 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 any authorized Lexus dealer or repair er, or another duly qualified and equipped
professional.
●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 any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.

2934-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F00E_(EE)
Press the LDA switch to turn the LDA
system on.
The LDA indicator illuminates and a
message is displayed on the multi-infor-
mation display.
Press the LDA switch again to turn the
LDA system off.
When the LDA system is turned on or
off, operation of the LDA system contin-
ues in the same condition the next time
the hybrid system is started.
LDA indicator
The illumination condition of the
indicator informs the driver of the
system operation status.
Illuminated in white:
LDA system is operating.
Illuminated in green:
Steering wheel assistance of the steer-
ing control 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 control function is
operating.
Turning LDA system on
Indications on multi-information display
1
2

2944-5. Using the driving support systems
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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.
• LDA is turned on.
• Vehicle speed is approximately 50 km/h (32 mph) or more.
•System recognizes white (yellow) lines.
• Width of traffic lane is approximately 3 m (9.8 ft.) 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 150 m (492 ft.).
• No system malfunctions are detected. ( →P. 2 9 7 )
●Steering control 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. 111)
• Vehicle is not accelerated or decelerated by a fixed amount or more.
• Steering wheel is not operated with a steering force level suitable for changing
lanes.
• ABS, VSC, TRC and PCS (Pre-Crash Safety system) are not operating.
• TRC or VSC is not turned off.
• Except for Israel: Hands off steering wheel alert is not displayed. ( →P. 2 9 5 )
3
XInside of displayed white lines is
whiteXInside 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.

2954-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F00E_(EE)
●Ve h i c l e s w a y w a r n i n g
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. 111)
• Vehicle speed is approximately 50 km/h (32 mph) or more.
• Width of traffic lane is approximately 3 m (9.8 ft.) or more.
• No system malfunctions are detected. ( →P. 2 9 7 )
■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, operation of the function is auto-
matically restored. ( →P. 2 9 4 )
■Steering control function
Depending on the vehicle speed, lane departure situation, road conditions, etc., the
operation of the functions may not be reco gnized or the functions may not operate.
■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.
■Hands off steering wheel alert
Except for Israel: When the system determines that the driver has removed their hands
from the steering wheel while the steering co ntrol function is operating, a warning mes-
sage is displayed on the multi-information display.
If the driver continues to keep their hands off of the steering wheel, the buzzer sounds, a
warning message is displayed and the function is temporarily canceled. This alert also
operates in the same way when the vehicle is driven with the steering wheel lightly
gripped. However, depending on the road conditions, etc., the function may not cancel.
For Israel: When the system determines that the driver has removed their hands from the
steering wheel while the lane departure control function or lane centering function is
operating, a warning message is displayed on the multi-information display and the
buzzer sounds.
■White (yellow) lines are only on one side of road
The LDA system will not operate for the side on which white (yellow) lines could not be
recognized.

2964-5. Using the driving support systems
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■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, “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 t ilts 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 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 lanes or crossed an intersection.
●Snow tires, etc., are equipped.

2974-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F00E_(EE)
■Warning message
Warning messages are used to indicate a system malfunction or to inform the driver of
the need for caution while driving. ( →P. 4 8 2 )
■Customization
The following settings can be changed.
For how to change settings, refer to P. 581.
FunctionSetting details
Lane departure alert functionAdjust alert sensitivity
Adjust alert type
Steering control functionTurn steering wheel assistance on and off
Vehicle sway warningTurn function on and off
Adjust alert sensitivity

2984-5. Using the driving support systems
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RSA (Road Sign Assist)∗
RSA recognizes specific road signs
using the camera sensor and provides
information to the driver via the multi-
information display.
If the system judges that the vehicle is being driven over the speed limit, perform-
ing prohibited actions, etc., in relation to the recognized road signs, it alerts the
driver using a warning display and warning buzzer
*.
*: This setting needs to be customized.
∗: If equipped
Summary of function
Camera sensor
WA R N I N G
■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 aware-
ness. Drive safely by always paying careful attention to the traffic rules.
Inappropriate or negligent driving could lead to an unexpected accident.

2994-5. Using the driving support systems
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Driving
GS450h_300h_OM_OM30F00E_(EE)
After the camera sensor recognizes a sign, it is displayed on the multi-informa-
tion display when the vehicle passes the sign.
●When the driving assist system infor-
mation is selected, a maximum of 3
signs can be displayed. (→P. 111)
●When other than the driving assist
system information is selected, a
speed limit sign or an all canceled
sign can be displayed. ( →P. 111)
A no overtaking sign and a speed
limit sign with supplemental mark are
not displayed. However, if signs other
than speed limit signs are recog-
nized, they are mentioned in a stack
under the current speed limit sign.
Indication on the mult i-information display

3004-5. Using the driving support systems
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The following types of road signs, including electronic signs and blinking signs,
are recognized.
*: If the turn signal indicator is not operated when changing lanes, the mark does not dis-play.
Types of recognized road signs
Ty p eMulti-information display
Speed limit begins/ends
Speed limit with sup- plemental mark
(Displayed simulta- neously with speed limit)
(Display example)
We t
Rain
Ice
On/off ramp*
Supplemental mark exists
(Contents not recog- nized)
No overtaking begins/ends
No-entry
All canceled
(All restrictions canceled. Returns to default
road regulation.)