2013 Lexus GS450h sensor

GS450h_U (OM30D01U)
2454-5. Using the driving support systems
4
Driving
■Automatic cancelation of constant speed control
The cruise control will stop maintaining the vehicle speed in the following situations:
●Actual vehicle speed is more than approximately 10 mph (16 km/h) below the set
vehicle speed.
At this time, the memorized set speed is not retained.
●Vehicle speed falls below approximately 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turned off by pressing the VSC OFF switch.
■When the LKA (Lane-Keeping Assist) will be activated
Using the radar cruise control in vehicle-to-vehicle distance control mode, lane
keeping assistance control is activated.
■Radar sensor and grille cover
Always keep the sensor and grille cover clean to ensure that the vehicle-to-vehicle
distance control operates properly. (Some ob structions, such as snow, ice and plastic
objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is cance led if an obstruction is detected.
■Warning messages and buzzers for dynamic radar cruise control
Warning messages and buzzers are used to indicate a system malfunction or to
inform the driver of the need for caution while driving. ( P. 7 2 3 )
Grille cover
Radar sensor
1
2

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
CAUTION
■To avoid inadvertent cruise control activation
Switch the cruise control off using the “ON/OFF” button when not in use.
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following situations.
Doing so may result in inappropriate sp eed control and could cause an accident
resulting in death or serious injury.
●In heavy traffic
●On roads with sharp bends
●On winding roads
●On slippery roads, such as those 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 expressways
●When weather conditions are bad enough that they may prevent the sensors
from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
●When an approach warning buzzer is heard often
●During emergency towing

GS450h_U (OM30D01U)
2494-5. Using the driving support systems
4
Driving
CAUTION
■When the 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 correc tly detect these types of vehicles, the
approach warning ( P. 242) will not be activated, and a fatal or serious accident
may result.
●Vehicles that cut in suddenly
●Vehicles traveling at low speeds
●Vehicles that are not moving
●Vehicles with small rear ends (trailers with no load on board etc.)
●Motorcycles traveling in the same lane
■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 thrown up by the surrounding vehicles hinders the function-
ing of the sensor
●When your vehicle is pointing upwards (caused by 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 of you decelerates suddenly

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
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 a 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 them with non-genuine parts.

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GS450h_U (OM30D01U)4-5. Using the driving support systems
4
Driving
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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GS450h_U (OM30D01U)
4-5. Using the driving support systems
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. 236) 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 5 6 )
Functions included in the LKA
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GS450h_U (OM30D01U)
4-5. Using the driving support systems
■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. 7 3 5 )
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 5 1 )
becomes suitable for its operation, the functions will begin to operate.

GS450h_U (OM30D01U)
2574-5. Using the driving support systems
4
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