lane assist Lexus GS450h 2017 User Guide

2824-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
LKA (Lane-Keeping Assist)
When driving on highways and freeways with white or yellow lines, this function
alerts the driver when the vehicle might depart from its lane and provides assis-
tance by operating the steering wheel to keep the vehicle in its lane. Further-
more, the system also provides steering assistance when dynamic radar cruise
control with full-speed range is operating to keep the vehicle in its lane.
The LKA system recognizes visible
white or yellow lines with the camera
sensor on the upper portion of the front
windshield.
◆Lane departure alert function
When the system determines that
the vehicle might depart from its
lane, a warning is displayed on the
multi-information display, and either
the warning buzzer sounds or the
steering wheel vibrates to alert the
driver.
When the warning buzzer sounds or the steering wheel vibrates, check
the surrounding road situation and carefully operate the steering wheelto move the vehicle back to the cen-
ter of the lane.
: If equipped
Summary of functions
Functions included in LKA system

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Driving
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◆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.
For Israel: If the system detects that the steering wheel has not beenoperated for a fixed amount of time
or the steering wheel is not being firmly gripped, a warning is displayedon the multi-information display and
the warning buzzer sounds.
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 notbeing firmly gripped, a warning is dis-
played on the multi-information dis- play and the function is temporarilycanceled.
◆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.

2844-5. Using the driving support systems
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◆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.
For Israel: If the system detects that the steering wheel has not beenoperated for a fixed amount of time
or the steering wheel is not being firmly gripped, a warning is displayedon the multi-information display and
the warning buzzer sounds.
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 notbeing firmly gripped, a warning is dis-
played on the multi-information dis- play and the function is temporarilycanceled.

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Press the LKA switch to turn the LKA
system on.
The LKA indicator illuminates and a
message is displayed on the multi-infor- mation 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 contin-
ues in the same condition the next time the hybrid system 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
Indications on multi-information display
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GS450h_300h_OM_OM30F92E_(EE)
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 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. 290)
●Steering assist function
This function operates when all of the follo wing conditions are met in addition to the operation conditions for the la ne 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. 289)
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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.

2884-5. Using the driving support systems
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●Vehicle sway warning
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. 290)
●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. 111)
• System recognizes white (yellow) lines. • Dynamic radar cruise control with full-speed range is operating.• Width of traffic lane is approximat ely 2.5 to 4.1 m (8.2 to 13.5 ft.).
• Turn signal lever is not operated. • Vehicle is driven on a straight road or around a gentle curve with a radius of morethan approximately 200 m (656 ft.).
• No system malfunctions are detected. ( P. 290) • Vehicle does not accelerate or dece lerate 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. 289) • 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, operation of the function is auto-
matically restored. ( P. 287)
■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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■Hands off steering wheel alert
For Israel: 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 and the buzzer sounds.
Except for Israel: 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 displa yed on the multi-information display. If the driver continues to keep the hands off of the steering wheel, the buzzer sounds, awarning 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.
■White (yellow) lines are on ly 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 functi ons 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 paralle l 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.

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●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 syst em malfunction or to inform the driver of the need for caution while driving. ( P. 466)
■Customization
The following settings can be changed.
For how to change settings, refer to P. 561.
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

3144-5. Using the driving support systems
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BSM (Blind Spot Monitor)
The Blind Spot Monitor is a system that has 2 functions;
●The Blind Spot Monitor function
Assists the driver in making the decision when changing lanes
●The Rear Crossing Traffic Alert function
Assists the driver when backing up
These functions use same sensors.
Switching the BSM function
The Blind Spot Monitor function and Rear Crossing Traffic Alert function can be switched on and off using the multi-information display. (P. 315)
When switched on, the BS M indicator illuminates on the meter and the buzzer
sounds.
Outside rear view mirror indicators
Blind Spot Monitor function: When a vehicle is detected in the blind spot, the outside rear view mirror indicator comes on while the turn signal lever is not op erated. If the turn signal lever is operated
toward the detected side, the outside rear view mirror indicator flashes.
Rear Crossing Traffic Alert function: When a vehicle approaching from the right or left rear of the vehicle is detected, the
outside rear view mirror indicators flash.
Rear Crossing Traffic Alert buzzer (Rear Crossing Traffic Alert function only)
When a vehicle approaching from the right or left rear of the vehicle is detected, a
buzzer sounds from behind the rear seat.
: If equipped
Summary of the Blind Spot Monitor
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GS450h_300h_OM_OM30F92E_(EE)
■Automatic system cancelation of hill-start assist control
The hill-start assist control will be canc eled in any of the following situations;
●The shift lever is shifted to N or P.
●The accelerator pedal is depressed.
●The parking brake is engaged.
●Approximately 2 seconds elapse after the brake pedal is released.
■Operating conditions of emergency brake signal
When the following three conditions are me t, the emergency brake signal will operate:
●The emergency flashers are off.
●Actual vehicle speed is over 55 km/h (35 mph).
●The brake pedal is depressed in a manner that cause the system to judge from the vehi- cle deceleration that this is a sudden braking operation.
■Automatic system cancelation of emergency brake signal
The emergency brake signal will turn of f in any of the following situations:
●The emergency flashers are turned on.
●The brake pedal is released.
●The system judges from the vehicle deceleration that is not a sudden braking operation.
WARNING
■The ABS does not operate effectively when
●The limits of tire gripping performance have been exceeded (such as excessively
worn tires on a snow covered road).
●The vehicle hydroplanes while driving at high speed on wet or slick roads.
■Stopping distance when the ABS is operating may exceed that of normal conditions
The ABS is not designed to shorten the vehicle’s stopping distance. Always maintain a safe distance from the vehicle in front of you, especially in the following situations:
●When driving on dirt, gravel or snow-covered roads
●When driving with tire chains
●When driving over bumps in the road
●When driving over roads with potholes or uneven surfaces
■TRC may not operate effectively when
Directional control and power may not be achievable while driving on slippery road surfaces, even if the TRC system is operating.
Drive the vehicle carefully in conditions where stability and power may be lost.
■Hill-start assist control does not operate effectively when
●Do not overly rely on the hill-start assist control. The hill-start assist control may not
operate effectively on steep inclines and roads covered with ice.
●Unlike the parking brake, hill-start assist co ntrol is not intended to hold the vehicle stationary for an extended period of time. Do not attempt to use hill-start assist con-
trol to hold the vehicle on an incline, as doing so may lead to an accident.