brake Lexus GS300h 2013 Workshop Manual

3364-5. Using the driving support system
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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. 308) 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-vehicle distance control may not
function correctly
Apply the brakes as necessary in the following conditions as the radar sen-
sor 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
functioning of the radar 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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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
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.

3604-5. Using the driving support system
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CAUTION
When using the Lexus parking assist-sensor
Observe the following precautions.
Failing to do so may result in the vehicle being unable to be driven safely
and possibly cause an accident.
Do not use the sensor at speeds in excess of 10 km/h (6 mph).
The sensors’ detection areas and reaction times are limited. When moving
forward or reversing, check the areas surrounding the vehicle (especially
the sides of the vehicle) for safety, and drive slowly, using the brake to
control the vehicle’s speed.
Do not install accessories within the sensors’ detection areas.
NOTICE
When using Lexus parking assist-sensor
In the following situations, the system may not function correctly due to a
sensor malfunction etc. Have the vehicle checked by any authorized Lexus
dealer or repairer, or another duly qualified and equipped professional.
The Lexus parking assist-sensor operation display flashes, and a beep
sounds when no obstacles are detected.
If the area around a sensor collides with something, or is subjected to
strong impact.
If the bumper collides with something.
If the display shows continuously without a beep.
If a display error occurs, first check the sensor.
If the error occurs even if there is no ice, snow or mud on the sensor, it is
likely that the sensor is malfunctioning.
Notes when washing the vehicle
Do not apply intensive bursts of water or steam to the sensor area.
Doing so may result in the sensor malfunctioning.

3884-5. Using the driving support system
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CAUTION
When using the Lexus parking assist monitor system
The Lexus parking assist monitor is a supplemental device intended to
assist the driver when backing up. When backing up, be sure to check visu-
ally behind and all around the vehicle before proceeding.
Observe the following precautions to avoid an accident that could result in
death or serious injuries.
Never depend on the Lexus parking assist monitor entirely when backing
up. The image and the position of the guide lines displayed on the screen
may differ from the actual state.
Use caution, just as you would when backing up any vehicle.
Be sure to back up slowly, depressing the brake pedal to control vehicle
speed.
If you seem likely to hit nearby vehicles, obstacles, people or mount the
shoulder, depress the brake pedal to stop the vehicle, then disable the
assist system by select on the screen to cancel the system.
The instructions given are only guidelines.
When and how much to turn the steering wheel will vary according to
traffic conditions, road surface conditions, vehicle condition, etc. when
parking. It is necessary to be fully aware of this before using the parking
assist system.
When parking, be sure to check that the parking space will accommodate
your vehicle before maneuvering into it.
Do not use the Lexus parking assist monitor in the following cases:
• On icy or slick road surfaces, or in snow
• When using tire chains or emergency tires
• When the trunk lid is not closed completely
• On roads that are not flat or straight, such as curves or slopes.

3974-5. Using the driving support system
4
Driving
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Driving assist systems
ABS (Anti-lock Brake System)
Helps to prevent wheel lock when the brakes are applied sud-
denly, or if the brakes are applied while driving on a slippery
road surface
Brake assist
Generates an increased level of braking force after the brake
pedal is depressed when the system detects a panic stop situation
VSC (Vehicle Stability Control)
Helps the driver to control skidding when swerving suddenly or
turning on slippery road surfaces
TRC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from
spinning when starting the vehicle or accelerating on slippery
roads
VGRS (Variable Gear Ratio Steering) (if equipped)
Adjusts the front wheel turning angle in accordance with the
vehicle speed and steering wheel movement
To help enhance driving safety and performance, the following
systems operate automatically in response to various driving situa-
tions. Be aware, however, that these systems are supplementary
and should not be relied upon too heavily when operating the vehi-
cle.

3984-5. Using the driving support system
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DRS (Dynamic Rear Steering) (if equipped)
Contributes to the turning characteristics and responsiveness of
the vehicle by slightly adjusting the rear wheel angle of the vehi-
cle in accordance with steering wheel movement
EPS (Electric Power Steering)
Employs an electric motor to reduce the amount of effort needed
to turn the steering wheel
AVS (Adaptive Variable Suspension system) (if equipped)
By independently controlling the damping force of the shock
absorbers for each of the 4 wheels according to the road and driv-
ing conditions, this system helps riding comfort with superior
steering stability, and helps good vehicle posture
When SPORT S+ mode is selected by the driving mode select
switch, the damping force is suitable for sporty driving (P.
394)
LDH (Lexus Dynamic Handling system) (if equipped)
Provides independent control of the VGRS, DRS and EPS. Con-
tributes to turning characteristics at low speeds, responsiveness
at medium speeds and safety at high speeds by controlling the
steering angle of the front and rear wheels in accordance with the
steering wheel operation and vehicle speed
VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRC, VSC,
EPS, VGRS (if equipped) and DRS (if equipped) systems
Helps to maintain vehicle stability when swerving on slippery
road surfaces by controlling the brakes, hybrid system output,
steering assist, and steering ratio and rear wheel angle

3994-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
PCS (Pre-Crash Safety system) (if equipped)
P. 406
Emergency brake signal
When the brakes are applied suddenly, the stop lights automati-
cally flash to alert the vehicle behind

4024-5. Using the driving support system
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When the message is displayed on the multi-information display showing that
TRC has been disabled even if the VSC OFF switch has not been pressed
TRC cannot be operated. Contact any authorized Lexus dealer or repairer, or
another duly qualified and equipped professional.
VGRS is disabled when
VGRS may stop operating in the following situations.
In this event, the steering wheel may move from its straight forward position,
but it will return when the system restarts.
The steering wheel is operated for an extended period of time while the
vehicle is stopped or is moving very slowly.
When force is continuously applied for a long time with the steering wheel
turned as far as it will go.
The center position of the steering wheel may change when VGRS is dis-
abled. However, the position will return to normal after VGRS is reacti-
vated.
When the 12-volt battery is disconnected
The steering wheel may move from its straight forward position, but this will
be corrected automatically when driving.
Sounds and vibrations caused by the ABS, brake assist, VSC, TRC and
VGRS systems
A sound may be heard from the engine compartment when the brake pedal
is depressed repeatedly, when the hybrid system is started or just after the
vehicle begins to move. This sound does not indicate that a malfunction has
occurred in any of these systems.
Any of the following conditions may occur when the above systems are
operating. None of these indicates that a malfunction has occurred.
• Vibrations may be felt through the vehicle body and steering.
• A motor sound may be heard after the vehicle comes to a stop.
EPS, VGRS and DRS operation sound
When the steering wheel is operated, a motor sound (whirring sound) may be
heard. This does not indicate a malfunction.
Reactivation of the TRC/VSC systems
Even after the TRC/VSC systems have been turned off, turning the hybrid
system off and then on again will automatically reactivate the TRC/VSC sys-
tems.

4034-5. Using the driving support system
4
Driving
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Reactivation of the TRC system linked to vehicle speed
When only the TRC system is turned off, the TRC system will turn on when
vehicle speed increases. However, when both TRC and VSC systems are
turned off, the systems will not turn on even when vehicle speed increases.
Reduced effectiveness of the EPS system
The effectiveness of the EPS system is reduced to prevent the system from
overheating when there is frequent steering input over an extended period of
time. The steering wheel may feel heavy as a result.
* Should this occur,
refrain from excessive steering input or stop the vehicle and turn the hybrid
system off. The EPS system should return to normal within 10 minutes.
*: If the LKA (Lane-Keeping Assist) system cannot operate in this case, a
warning message will be shown on the multi-information display.
Operating conditions of emergency brake signal
When the following three conditions are met, 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 vehicle deceleration that this is a sudden braking operation.
Automatic system cancelation of emergency brake signal
The emergency brake signal will turn off 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 brak-
ing operation.

4064-5. Using the driving support system
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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 the possibility of a frontal collision,
the pre-crash safety system 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. 408)