2015 Lexus GS450h sensor

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Driving
CAUTION
■When the radar sensor may not be correctly detecting the vehicle ahead
Apply the brakes as necessary when any of the following types of vehicles are in
front of you.
As the sensor may not be able to correctly detect these types of vehicles, the
approach warning ( P. 262) will not be activated, and a fatal or serious accident
may result.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Motorcycles traveling in the same lane
●Vehicles that are not moving
●Vehicles with small rear ends (trailers with no load on board etc.)
●Details about other people/objects the system will not detect:
 P. 2 6 7
■Conditions under which the vehicle-to-veh icle distance control may not function
correctly
Apply the brakes as necessary in the following conditions as the radar sensor may
not be able to correctly detect vehicles ahead, and a fatal or serious accident may
result:
●When water or snow splashed by the su rrounding vehicles hinders the function-
ing of the radar sensor
●When your vehicle is tilted upwards (due to a heavy load in the trunk etc.)
●When the road curves or when the lanes are narrow
●When steering wheel operation or your position in the lane is unstable
●When the vehicle ahead decelerates suddenly as the system is not able to
respond to sudden braking.
Details about limitations:
 P. 2 6 7
Details about unsuitable conditions:
 P. 2 6 8

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CAUTION
■Handling the radar sensor
Observe the following to ensure the cruise control system can function effectively.
Otherwise, the system may not function co rrectly and could result in an accident.
●Keep the sensor and grille cover clean at all times.
Clean the sensor and grille cover with a soft cloth so you do not mark or damage
them.
●Do not subject the sensor or surr ounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunction. If the
sensor or surrounding area is subject to a strong impact, always have the area
inspected and adjusted by your Lexus dealer.
●Do not disassemble the sensor.
●Do not attach accessories or stickers to the sensor, grille cover or surrounding
area.
●Do not modify or paint th e sensor and grille cover.
●Do not replace the sensor or grill cover with non-genuine parts.

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LKA (Lane-Keeping Assist)
While driving on a freeway or motor highway that has lane markers and
no sharp curves, the sy stem recognizes the lane s using a camera located
above the inside rear view mirror as a sensor to assist the driver with stay-
ing in the lane. The LKA system has two functions.
Camera sensor

: If equipped
Summary of functions

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Lane departure warning function
If the system judges that the vehicle may deviate from its lane, it alerts
the driver using beeping, screen displays and a sensory warning
* given
via the steering wheel.
*: A slight steering torque is applied for a short period of time in the direction of
the center of the lane.
Lane keeping assist function• This function will be active when the vehicle-to-vehicle distance con- trol mode of the cruise control (P. 240) is set with vehicle speed
above approximately 45 mph (72 km/h) and while the lane depar-
ture warning function is active.
• When the lane keeping assist fu nction is active, a slight steering
torque will be applied, to help the driver maintain the vehicle inside
the lane.
The lane keeping assist function will be temporarily canceled if the steering
wheel is not operated, or if you continue driving with your hands lightly touch-
ing the steering wheel. ( P. 2 76 )
Functions included in the LKA
1
2

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■Temporary cancelation of the LKA system functions
If any of the following occurs, the LKA system functions will be temporarily canceled.
The functions will resume after the necessary operating conditions have returned.
●The steering wheel is turned as far as necessary to cause the vehicle to change
lanes.
●When the system detects no-handed driving. (The lane keeping assist function will
be temporarily canceled, but the lane departure warning function will continue.)
●The turn signal lever is operated.
●The vehicle speed deviates from the operating range of the LKA system functions.
(The buzzer will beep twice when the lane keeping assist function is being can-
celed.)
●When the lane lines cannot be recognized while driving. (The buzzer will beep
twice when the lane keeping assist function is being canceled.)
●The wiper switch is set on high speed mode or is set on AUTO mode with wipers
operating at high speed. (The lane keeping assist function will be temporarily can-
celed, but the lane departure warning function will continue.)
●If the vehicle crosses a line for approximately half a minute or more. (The lane keep-
ing assist function will be temporarily canceled, but the lane departure warning
function will continue.)
●When the lane departure warning function is activated.
The lane departure warning function will not operate again for a several seconds
after it has been activated, even if the vehicle leaves the lane again.
■The lane departure warning
It may be difficult to feel the sensory warning depending on the road conditions.
■No-handed driving warning
If the steering wheel is not operated for approximately 15 seconds on a straight road
or approximately 5 seconds on a curve, the buzzer will beep twice, indicators on the
multi-information display will flash, and the lane keeping assist function will be tem-
porarily canceled. If you drive the vehicle with your hands lightly touching the steer-
ing wheel, this may also be detected as no-handed driving.
■After the vehicle has been parked in the sun
The LKA system functions may not be available and a warning message ( P. 5 2 6 )
will be displayed for a while after driving ha s started. In such cases, turn the LKA sys-
tem off and turn it on again after normal temperature returns. When the temperature
in the cabin decreases and the temperature around the camera sensor ( P. 2 7 1 )
becomes suitable for its operation, the functions will begin to operate.

GS450h_OM_OM30E26U_(U)
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Driving
■If there are lane markers on only one side of the vehicle
The lane keeping assist function will not operate. Also, the lane departure warning
will not operate for the side on which lane markers could not be recognized.
■Conditions in which the function may not operate correctly
In the following conditions, the LKA system functions may not operate, or it may not
be possible to ensure adequate performance. Also, the camera sensor may be
unable to recognize lane lines causing the lane departure warning function to oper-
ate incorrectly, or the lane keeping assist function may not operate properly. How-
ever, this does not indicate a malfunction.
●When driving through an area with no lane markers, such as a tollbooth, a crossing
or before a ticket checkpoint
●When driving on a sharp curve
●When lanes are extremely narrow or extremely wide
●When the vehicle leans to one side an unusual amount due to a heavy load or
improper tire inflation pressure
●When the following distance between your vehicle and the vehicle ahead is
extremely short
●When the lane markers are yellow (These may be more difficult for the system to
recognize compared to white markers.)
●When the lane markers are broken, “Botts’ dots”, “Raised pavement marker” or
stones
●When lane markers are obscured or pa rtially obscured by sand, dirt, etc.
●When there are shadows on the road running parallel with lane markers, or if a
shadow covers the lane markers
●When driving on a particularly bright road surface, such as concrete
●When driving on a road surface that is bright due to reflected light
●When driving in a location where the light level changes rapidly, such as the
entrance to or exit from a tunnel
●When sunlight or the headlights of oncoming vehicles are shining directly into the
camera lens
●When driving on roads that are branching or merging
●When driving on a road surface that is wet due to rain, previous rainfall, standing
water, etc.
●When the vehicle experiences strong up-a nd-down motion such as when driving
on an extremely rough road or on a seam in the pavement
●When headlight brightness at nighttime is reduced due to dirt on the lenses, or
when the headlights are misaligned
●When driving with a strong crosswind

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NOTICE
■Camera sensor (P. 2 7 1 )
Observe the following to ensure that the LKA system functions correctly.
●Keep the windshield clean at all times.
Performance could be affected if the windshield is dirty, or if raindrops, conden-
sation or ice are adhering to the windshield.
●When adjusting the rear view mirror, make sure that it does not block the camera
lens.
●Do not attach window tinting to the windshield.
●Do not install an antenna in front of the camera lens.
●If the windshield is fogged up, use the windshield defogger to remove fog from
the windshield.
When it is cold, using the heater with ai r blowing to the feet may allow the upper
part of the windshield to fog up. This will have a negative effect on the images.
●Do not place anything on the dashboard.
The camera sensor may recognize the image reflected on the windshield as lane
markers by mistake.
●Do not scratch the camera lens, or let it get dirty.
When cleaning the inside of the windshield, be careful not to get any glass
cleaner etc. on the lens. Also, do not touch the lens.
For lens repair, contact your Lexus dealer.
●Do not change the installation position or direction of the camera sensor or
remove it. The direction of the camera sensor is precisely adjusted.
●Do not subject the camera sensor to stro ng impact or force, and do not disas-
semble the camera sensor.
●Do not attach a sticker or other items to the
windshield near the camera sensor.
●Do not install or place anything near the
camera.

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PCS (Pre-Collision System)
◆Pre-collision seat belts (front seat only)
If the pre-collision sensor detects that a collision is unavoidable, the
pre-collision system will retract the seat belt before the collision occurs.
The same will happen if the dr iver makes an emergency braking or
loses control of the vehicle. ( P. 3 4 )
◆Pre-collision brake assist
When there is a high possibility of a frontal collision, the system applies
greater braking force in relation to how strongly the brake pedal is
depressed.
◆Pre-collision braking
When there is a high poss ibility of a frontal collision, the system warns
the driver using a warning light, war ning display and buzzer. If the sys-
tem determines that a collision is unavoidable, the brakes are automati-
cally applied to reduce the collision speed.

: If equipped
When the radar sensor detects the possibility of a frontal collision, the
pre-collision system such as the brakes and seat belts are automatically
engaged to lessen impact as well as vehicle damage.
The pre-collision system ca n be turned on and off as necessary by oper-
ating the switch. ( P. 2 9 3 )