brakes Lexus GS450h 2015 Opening, closing and locking the doors and trunk / LEXUS 2015 GS450H FROM MAR. 2015 PROD. (OM30F70U) User Guide

GS450h_OM_OM30F70U_(U)
2454-5. Using the driving support systems
4
Driving
Example of follow-up cruising
When following a vehicle driving slower than the set speed
The system continues follow-up cruising while adjusting for changes in the speed
of the vehicle ahead in order to maintain the vehicle-to-vehicle distance set by the
driver.
Example of acceleration
When there are no longer any vehi cles ahead driving slower than the
set speed
The system accelerates until the set speed is reached. The system then returns to
constant speed cruising.
When your vehicle is too close to a vehicle ahead, and sufficient auto-
matic deceleration via the cruise co ntrol is not possible, the display will
flash and the buzzer will sound to alert the driver. An example of this
would be if another driver cuts in front of you while you are following a
vehicle. Apply the brakes to ensure an appropriate vehicle-to-vehicle dis-
tance.
■Warnings may not occur when
In the following instance s, there is a possibility that the warnings will not
occur:
●When the speed of the vehicle ahea d matches or exceeds your vehi-
cle speed
●When the vehicle ahead is traveling at an extremely slow speed
●Immediately after the cruise control speed was set
●At the instant the accelerator is applied
Approach warning
3
4

250
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
CAUTION
■Before using dynamic radar cruise control
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set speed. If automatic deceleration/acceleration is not appropri-
ate, adjust the vehicle speed, as well as the distance between your vehicle and vehi-
cles ahead by applying the brakes etc.
■Cautions regarding the driving assist systems
Observe the following precautions.
Failure to do so may cause an accident resulting in death or serious injury.
●Assisting the driver to measure following distance
The dynamic radar cruise control is only intended to help the driver in determin-
ing the following distance between the driver’s own vehicle and a designated
vehicle traveling ahead. It is not a mechanism that allows careless or inattentive
driving, and it is not a system that can assi st the driver in low-visibility conditions. It
is still necessary for driver to pay close attention to the vehicle’s surroundings.
●Assisting the driver to judge proper following distance
The dynamic radar cruise control determines whether the following distance
between the driver’s own vehicle and a designated vehicle traveling ahead is
appropriate or not. It is not capable of making any other type of judgement.
Therefore, it is absolutely necessary for the driver to remain vigilant and to deter-
mine whether or not there is a possibility of danger in any given situation.
●Assisting the driver to operate the vehicle
The dynamic radar cruise control has no capability to prevent or avoid a collision
with a vehicle traveling ahead. Therefore, if there is ever any danger, the driver
must take immediate and direct control of the vehicle and act appropriately in
order to ensure the safety of all involved.

252
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
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. 245) 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

GS450h_OM_OM30F70U_(U)
2594-5. Using the driving support systems
4
Driving
Pulling the lever toward you can-
cels the cruise control.
The setting is also canceled when the
brake pedal is depressed while driv-
ing.
(When the vehicle has been stopped
by system control, applying the brakes
does not cancel the setting.)
Pushing the lever up resumes the
cruise control and returns vehicle
speed to the set speed.
However, when a vehicle ahead is not
detected in vehicle-to-vehicle dis-
tance control mode, cruise control
does not resume when the actual vehi-
cle speed is approximately 25 mph
(40 km/h) or less. Also, when the
vehicle is in constant speed control
mode and the actual vehicle speed is
approximately 25 mph (40 km/h) or
less, cruise control does not resume as
the set speed is cleared.
Canceling and resuming the speed control
1
2

260
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
This mode employs a radar sensor to detect the presence of vehicles up to
approximately 400 ft. (120 m) ahead, determines the current vehicle-to-
vehicle following distance, and opera tes to maintain a suitable following
distance from the vehicle ahead.
Note that vehicle-to-vehicle distance will close in when traveling on long downhill
slopes.
Example of constant speed cruising
When there are no vehicles ahead
The vehicle travels at the speed set by the driver. The desired vehicle-to-vehicle
distance can also be set by operating the vehicle-to-vehicle distance control.
Example of deceleration cruising and follow-up cruising
When the vehicle ahead is driving slower than the set speed
When a vehicle is detected running ahead of you, the system automatically decel-
erates your vehicle. When a greater reduction in vehicle speed is necessary, the
system applies the brakes. The system will respond to changes in the speed of the
vehicle ahead in order to maintain the vehicle-to-vehicle distance set by the
driver. A warning tone warns you when the system cannot decelerate sufficiently
to prevent your vehicle from closing in on the vehicle ahead. When the vehicle
ahead of you stops, your vehicle will also stop. After the vehicle ahead starts off,
pushing the cruise control lever up or depressing the accelerator pedal will
resume follow-up cruising.
Driving in vehicle-to-vehicle distance control mode
1
2

GS450h_OM_OM30F70U_(U)
2614-5. Using the driving support systems
4
Driving
Example of acceleration
When there are no longer any vehicles ahead driving slower than the
set speed
The system accelerates until the set speed is reached. The system then returns to
constant speed cruising.
When your vehicle is too close to a vehicle ahead, and sufficient auto-
matic deceleration via the cruise co ntrol is not possible, the display will
flash and the buzzer will sound to alert the driver. An example of this
would be if another driver cuts in front of you while you are following a
vehicle. Apply the brakes to ensure an appropriate vehicle-to-vehicle dis-
tance.
■Warnings may not occur when
In the following instance s, there is a possibility that the warnings will not
occur:
●When the speed of the vehicle ahea d matches or exceeds your vehi-
cle speed
●When the vehicle ahead is traveling at an extremely slow speed or is
stationary
●Immediately after the cruise control speed was set
●At the instant the accelerator is applied
Approach warning
3

266
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
CAUTION
Dynamic radar cruise control with full-speed range is designed to detect motor vehi-
cles intended for use on public highways, with the exception of motorcycles. It will not
detect: stationary objects, pedestrians, motorcycles, bicycles, animals, and similarly
sized, or smaller, moving objects. The dr iver must always be aware of surroundings
and in control of the vehicle.
■Before using dynamic radar cruise control with full-speed range
Do not overly rely on vehicle-to-vehicle distance control.
Be aware of the set vehicle speed. If automatic deceleration/acceleration is not
appropriate, adjust the vehicle speed, as well as the distance between your vehicle
and vehicles ahead by applying the brakes etc.
■Cautions regarding the driving assist systems
Observe the following precautions.
Failure to do so may cause an accident resulting in death or serious injury.
The system, even in vehicle-to-vehicle distance control mode, only assists the
driver:
●To measure following distance
The dynamic radar cruise control with fu ll-speed range is only intended to help
the driver in determining the following distance between the driver’s own vehicle
and a designated vehicle traveling ahead. It is not a mechanism that allows care-
less or inattentive driving, and it is not a system that can assist the driver in low-vis-
ibility conditions. It is still necessary for driver to pay close attention to the
vehicle’s surroundings.
●To judge proper following distance
The dynamic radar cruise control with fu ll-speed range determines whether the
following distance between the driver’s own vehicle and a designated vehicle
traveling ahead is appropriate or not. It is not capable of making any other type of
judgement. Therefore, it is absolutely ne cessary for the driver to remain vigilant
and to determine whether or not there is a possibility of danger in any given situa-
tion.
●To operate the vehicle
The dynamic radar cruise control with fu ll-speed range has no capability to pre-
vent or avoid a collision with a vehicle traveling ahead. Therefore, if there is ever
any danger, the driver must take immediat e and direct control of the vehicle and
act appropriately in order to ensu re the safety of all involved.

268
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
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. 261) 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 6
■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 6
Details about unsuitable conditions:
 P. 2 6 7

283
GS450h_OM_OM30F70U_(U)4-5. Using the driving support systems
4
Driving
Driving assist systems
◆ABS (Anti-lock Brake System)
Helps to prevent wheel lo ck when the brakes are applied suddenly, or if
the brakes are applied while dri ving on a slippery road surface
◆Brake assist
Generates an increased level of br aking 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
◆Enhanced VSC (Enhanced Vehicle Sta bility Control) (if equipped)
Provides cooperative control of the ABS, TRAC, VSC and EPS.
Helps to maintain directional stability when swerving on slippery road
surfaces by controllin g steering performance.
◆TRAC (Traction Control)
Helps to maintain drive power and prevent the drive wheels from spin-
ning when starting the vehicle or accelerating on slippery roads
◆VGRS (Variable Gear Ratio Steering) (if equipped)
Adjusts the front wheel turning angl e in accordance with the vehicle
speed and steering wheel movement
To help enhance driving safety an d performance, the following systems
operate automatically in response to various driving situations. Be
aware, however, that these systems are supplementary and should not
be relied upon too heavily when operating the vehicle.

284
GS450h_OM_OM30F70U_(U)
4-5. Using the driving support systems
◆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 vehicle in accor-
dance 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)
By independently controlling the damping force of the shock absorbers
for each of the 4 wheel s according to the road and driving 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. 280)
◆LDH (Lexus Dynamic Handlin g system) (if equipped)
Provides independent control of the VGRS, DRS and EPS. Contributes
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 accorda nce with the steering wheel opera-
tion and vehicle speed
◆VDIM (Vehicle Dynamics Integrated Management)
Provides integrated control of the ABS, brake assist, TRAC, VSC and
EPS, VGRS (if equipped) and DRS (if equipped) systems
Helps to maintain vehicle stability when swerving on slippery road sur-
faces by controlling the brakes, hybr id system output, steering assist,
and steering ratio
◆PCS (Pre-Collision System) (if equipped)
 P. 2 9 0