warning Lexus GS300h 2017 Owners Manual

2704-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
PCS (Pre-Crash Safety system) 
◆Pre-crash warning
When the system determines that
the possibility of a frontal collision is
high, a buzzer will sound and a warn-
ing message will be displayed on the
multi-information display to urge the
driver to take evasive action.
◆Pre-crash brake assist
When the system determines that the possibility of a frontal collision is high,
the system applies greater braking force in relation to how strongly the brake
pedal is depressed.
: If equipped
The pre-crash safety system uses a radar sensor and camera sensor to detect
vehicles and pedestrians *1
in front of your vehicle. When the system deter-
mines that the possibility of a frontal collision with a vehicle or pedestrian is
high, a warning operates to urge the dr iver to take evasive action and the
potential brake pressure is increased to help the driver avoid the collision. If
the system determines that the possibility of a frontal collision with a vehicle o r
pedestrian is extremely high, the brakes are automatically applied *2
to help
avoid the collision or help reduce the impact of the collision.
The pre-crash safety system can be disabled/enabled and the warning timing
can be changed. ( P. 273)
* 1
: Depending on the region in which the vehicle was sold, the pedestrian detection
function may not be available. Contact any authorized Lexus retailer or Lexus
authorized repairer, or any reliable repairer for details.
* 2
: Depending on the region in which the vehicle was sold, the pre-crash braking func-
tion (automatic braking function) may not be available. Contact any authorized
Lexus retailer or Lexus authorized repair er, or any reliable repairer for details.

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◆Pre-crash braking *3
When the system determines that the possibility of a frontal collision is high,
the system warns the driver. If the system determines that the possibility of a
frontal collision is extremely high, the brakes are automatically applied to h elp
avoid the collision or reduce the collision speed.
* 3
: Depending on the region in which the vehicle was sold, the pre-crash braking function
may not be available.
◆Suspension control (if equipped)
When the system determines that the possibility of a frontal collision is high,
the Adaptive Variable Suspension System ( P. 325) will control the damping
force of the shock absorbers to help maintain an appropriate vehicle posture.
◆Steering control (if equipped)
When the system determines that the possibility of a frontal collision is hi gh
and the driver is operating the steering wheel, the LDH system ( P. 325) will
control the turning angle of the front and rear wheels and effort necessary to
turn the steering wheel to help enhance steering responsiveness.
WARNING
■Limitations of the pre-crash safety system
●The driver is solely responsible for safe driving. Always drive safely, taking care to
observe your surroundings.
Do not use the pre-crash safety system instead of normal braking operations under
any circumstances. This system will not pr event collisions or lessen collision damage
or injury in every situation. Do not overly re ly on this system. Failure to do so may lead
to an accident, resulting in death or serious injury.
●Although this system is designed to help avoid a collision or help reduce the impact of
the collision, its effectiveness may change according to various conditions, therefore
the system may not always be able to achieve the same level of performance.
Read the following conditions carefully. Do not overly rely on this system and always
drive carefully.

2724-5. Using the driving support systems
GS450h_300h_OM_OM30F92E_(EE)
WARNING
■Pre-crash braking *3
●When the pre-crash braking function is operating, a large amount of braking force
will be applied.
●If the vehicle is stopped by the operation
of the pre-crash braking function, the pre-
crash braking function operation will be canceled after approximately 2 seconds.
Depress the brake pedal as necessary.
●The pre-crash braking function may not operate if certain operations are performed
by the driver. If the accelerator pedal is being depressed strongly or the steering
wheel is being turned, the system may determine that the driver is taking evasive
action and possibly prevent the pre-crash braking function from operating.
●In some situations, while the pre-crash brakin g function is operating, operation of the
function may be canceled if the accelerator pedal is depressed strongly or the steer-
ing wheel is turned and the system determines that the driver is taking evasive action.
●If the brake pedal is being depressed, the sy stem may determine that the driver is tak-
ing evasive action and possibly delay the op eration timing of the pre-crash braking
function.
* 3
: Depending on the region in which the vehicle was sold, the pre-c rash braking func-
tion may not be available.
■When to disable the pre-crash safety system
In the following situations, disable the syst em, as it may not operate properly, possibly
leading to an accident resulting in death or serious injury:
●When the vehicle is being towed
●When your vehicle is towing another vehicle
●When transporting the vehicle via truck, boat, train or similar means of transportation
●When the vehicle is raised on a lift with the hybrid system on and the tires are allowed
to rotate freely
●When inspecting the vehicle using a drum tester such as a chassis dynamometer or
speedometer tester, or when using an on vehicle wheel balancer
●When a strong impact is applied to the fron t bumper or front grille, due to an accident
or other reasons
●If the vehicle cannot be driven in a stable manner, such as when the vehicle has been
in an accident or is malfunctioning
●When the vehicle is driven in a sporty manner or off-road
●When the tires are not properly inflated
●When the tires are very worn
●When tires of a size other than specified are installed
●When tire chains are installed
●When a compact spare tire or an emergency tire puncture repair kit is used
●If equipment (snow plow, etc.) that may obstruct the radar sensor or camera sensor is
temporarily installed to the vehicle

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■Enabling/disabling the pre-crash safety system
The pre-crash safety system can be enabled/disabled on ( P. 111) of
the multi-information display. The system is automatically enabled each time the power switch is turned to ON
mode.
If the system is disabled, the PCS
warning light will turn on and a mes-
sage will be displayed on the multi-
information display.
■Changing the pre-crash warning timing
The pre-crash warning timing can be changed on ( P. 111) of the
multi-information display.
The operation timing setting is retained when the power switch is turned off.
Far
The warning will begin to operate
earlier than with the default timing.
Middle
This is the default setting.
Near
The warning will begin to operate
later than with the default timing.
Changing settings of the pre-crash safety system
1
2
3

2744-5. Using the driving support systems
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■Operational conditions
Availability of the pedestrian detection func tion and pre-crash braking function depend
on the region in which the vehicle was sold.
Read the following for details:
Region A
(The pedestrian detection function and pre-crash braking function are available)
The pre-crash safety system is enabled and th e system determines that the possibility of a
frontal collision with a vehicle or pedestrian is high.
Each function is operational at the following speeds:
●Pre-crash warning:

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Region B
(The pedestrian detection function is not available and the pre-crash braking function
is available)
The pre-crash safety system is enabled and th e system determines that the possibility of a
frontal collision with a vehicle is high.
Each function is operational at the following speeds:
●Pre-crash warning:

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4
: Depending on the region in which the vehicle was sold, the pedestrian detection
function may not be available.
■If the PCS warning light flashes and a warnin g message is displayed on the multi-infor-
mation display
The pre-crash safety system may be temporar ily unavailable or there may be a malfunc-
tion in the system.
●In the following situations, the warning light will turn off, the message will disappear and
the system will become operational when normal operating conditions return:

2824-5. Using the driving support systems
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LKA (Lane-Keeping Assist) 
When driving on highways and freeways with white or yellow l
ines, 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 wheel
to 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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◆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 been
operated for a fixed amount of time
or the steering wheel is not being
firmly gripped, a warning is displayed
on 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 not
being firmly gripped, a warning is dis-
played on the multi-information dis-
play and the function is temporarily
canceled.
◆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 been
operated for a fixed amount of time
or the steering wheel is not being
firmly gripped, a warning is displayed
on 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 not
being firmly gripped, a warning is dis-
played on the multi-information dis-
play and the function is temporarily
canceled.