2012 Lexus GS250 warning light

2754-5. Using the driving support
4
Driving
GS350/250_EE (OM30C36E)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 direc-
tion of the center of the lane.
Lane keeping assist function
• This function will be active when the vehicle-to-vehicle dis-
tance control mode of the cruise control (P. 258) is set with
vehicle speed above approximately 72 km/h (45 mph) and
while the lane departure warning function is active.
• When the lane keeping assist function is active, a slight steer-
ing torque will be applied, to help the driver maintain the vehi-
cle 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 touching the steering wheel. (P. 279)
Functions included in the LKA
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2794-5. Using the driving support
4
Driving
GS350/250_EE (OM30C36E)
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 func-
tion 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 func-
tion is being canceled.)
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 canceled, but the lane departure warning function will con-
tinue.)
If the vehicle crosses a line for approximately half a minute or more. (The
lane keeping 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 condi-
tions.
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 temporarily canceled. If you drive the vehicle
with your hands lightly touching the steering wheel, this may also be
detected as no-handed driving.

2804-5. Using the driving support
GS350/250_EE (OM30C36E)
After the vehicle has been parked in the sun
The LKA system functions may not be available and a warning message
(P. 767) will be displayed for a while after driving has started. In such
cases, turn the LKA system 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. 274) becomes suitable for its operation, the
functions will begin to operate.
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 rec-
ognized.
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 operate incorrectly, or the lane keeping assist function may not
operate properly. However, 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 sys-
tem to recognize compared to white markers.)
When the lane markers are broken, “Raised pavement marker” or stones
When lane markers are obscured or partially 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

2814-5. Using the driving support
4
Driving
GS350/250_EE (OM30C36E)
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-and-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
When driving on winding roads or roads that are uneven
When driving on rough or unpaved roads
When changing the tires
Depending on the tires used, sufficient performance may not be maintain-
able.
Warning messages for LKA
Warning messages are used to indicate a system malfunction or to inform the
driver of the need for caution while driving. (P. 760, 767)
CAUTION
Before using the LKA system
Do not rely solely on the LKA system. The LKA system does not drive the
vehicle automatically, nor does it reduce the amount of care you need to
take. As such, the driver must always assume full responsibility for under-
standing his/her surroundings, for operating the steering wheel to correct
the driving line, and for driving safely.
Inappropriate or negligent driving could lead to an accident.
To avoid operating the LKA by mistake
Switch the LKA off using the “LKA” switch when not in use.

2944-5. Using the driving support
GS350/250_EE (OM30C36E)
Lexus parking assist-sensor display
When an obstacle is detected while the rear view monitor system, is in use,
the warning indicator will appear in the top right of the screen even if the dis-
play setting has been set to off.
Sensor detection information
The sensor’s detection areas are limited to the areas around the vehicle’s
front corner and rear bumpers.
Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where
this may occur are listed below.
• There is dirt, snow or ice on the sensor. (Wiping the sensors will resolve
this problem.)
• The sensor is frozen. (Thawing the area will resolve this problem.)
In especially cold weather, if a sensor is frozen the screen may show an
abnormal display, or obstacles may not be detected.
• The sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle
engines, air brakes of large vehicles, or other loud noises producing
ultrasonic waves.
• There is another vehicle equipped with parking assist sensors in the
vicinity.
• The sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelets are installed.
• The bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather.
• The area directly under the bumpers is not detected.
• If obstacles draw too close to the sensor.
• A non-genuine Lexus suspension (lowered suspension etc.) is installed.
• People may not be detected if they are wearing certain types of clothing.
In addition to the examples above, there are instances in which, because of
their shape, signs and other objects may be judged by the sensor to be closer
than they are.

3434-5. Using the driving support
4
Driving
GS350/250_EE (OM30C36E)
PCS (Pre-Crash Safety system)
Pre-crash seat belts (front seat only)
If the pre-crash sensor detects that a collision is unavoidable, the
pre-crash safety system will retract the seat belt before the colli-
sion occurs.
The same will happen if the driver makes an emergency braking
or loses control of the vehicle. (P. 40)
Pre-crash 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-crash braking
When there is a high possibility of a frontal collision, the system
warns the driver using a warning light, warning display and
buzzer. If the system determines that a collision is unavoidable,
the brakes are automatically applied to reduce the collision
speed.

: If equipped
When the radar sensor detects that a frontal collision is highly
likely or even unavoidable, safety systems such as the brakes and
seat belts are automatically engaged to lessen impact as well as
vehicle damage.
The pre-crash safety system can be turned on and off as necessary
by operating the switch. (P. 344)

3444-5. Using the driving support
GS350/250_EE (OM30C36E)
Suspension control (if equipped)
When the system determines that a collision is unavoidable, the
operation of AVS (P. 334) optimally controls the damping
force of the shock absorber.
Driver monitor system (if equipped)
When the system determines that there is a possibility of a colli-
sion, and either the driver is not facing forward or the driver’s
eyes are closed, PCS warnings are given in advance to warn the
driver. If the system determines that the conditions to operate
pre-crash alert braking have been met even when the possibility
of a collision increases further, pre-crash alert braking will oper-
ate.
Enabled
Disabled
The “PCS” warning light comes on
when pre-crash safety system is
disabled.
Disabling pre-crash safety system
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3484-5. Using the driving support
GS350/250_EE (OM30C36E)
Situations in which the pre-crash safety system does not function properly
The system may not function effectively in situations such as the following:
On roads with sharp bends or uneven surfaces
If a vehicle suddenly moves in front of your vehicle, such as at an intersec-
tion
If a vehicle suddenly cuts in front of your vehicle, such as when overtaking
In inclement weather such as heavy rain, fog, snow or sand storms
When your vehicle is skidding such as the VSC system off
When your vehicle is steeply inclined
Automatic cancelation of the pre-crash safety system
When a malfunction occurs due to sensor contamination, etc. that results in
the sensors being unable to detect obstacles, the pre-crash safety system will
be automatically disabled. In this case, the system will not activate even if
there is a collision possibility.
When there is a malfunction in the system
“PCS” warning light will flash and warning messages will be displayed.
(P. 751, 759)