2015 Lexus GS450h cruise control

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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
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When constant speed control mode is selected, your vehicle will maintain
a set speed without controlling the vehi cle-to-vehicle distance. Select this
mode only when vehicle-to-vehicle distance control mode does not func-
tion correctly due to dirt etc.
Press the “ON/OFF” button to
activate the cruise control.
Press the button again to deactivate
the cruise control.
Switch to constant speed control
mode.
(Push the lever forward and hold
for approximately 1 second.)
Cruise control indicator will come on.
When in constant speed control
mode, to return to vehicle-to-vehicle
distance control mode, push the lever
forward again and hold for approxi-
mately 1 second.
After the desired speed has been set,
it is not possible to return to vehicle-
to-vehicle distance control mode.
If the power switch is turned off and
then turned to ON mode again, the
vehicle will automatically return to
vehicle-to-vehicle distance control
mode.
Adjusting the speed setting: P. 2 5 6
Canceling and resuming the speed
setting: P. 2 5 9
Selecting conventional constant speed control mode
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Driving
■Dynamic radar cruise control with full-speed range can be set when
●The shift lever is in D or range 4 or higher of S has been selected.
●Range 4 or higher of D has been selected by using the paddle shift.
●Vehicle speed is above approximately 30 mph (50 km/h).
■Accelerating after setting the vehicle speed
The vehicle can accelerate normally. After acceleration, the set speed resumes.
However, during vehicle-to-vehicle distance control mode, the vehicle speed may
decrease below the set speed in order to maintain the distance to the vehicle ahead.
■Automatic cancelation of vehicle-to-vehicle distance control
Vehicle-to-vehicle distance control driving is automatically canceled in the following
situations:
●Actual vehicle speed falls below approximately 25 mph (40 km/h) when there are
no vehicle ahead.
●The preceding vehicle leaves the lane when your vehicle is following at a speed
below 25 mph (40 km/h).
●VSC is activated.
●TRAC is activated for a period of time.
●When the VSC or TRAC system is turn ed off by pressing the VSC OFF switch.
●The sensor cannot operate correctly because it is covered in some way.
●The windshield wipers are operating at hi gh speed (when the wiper switch is set to
AUTO mode or the high speed wiper operation).
●When snow mode is set.
●The parking brake is operated.
●The vehicle is stopped by system control on a steep incline.
●Pre-collision brake assist is activated.
●The following are detected when the vehi cle has been stopped by system control:
• The driver is not wearing a seat belt.
• The driver’s door is opened.
• The trunk or hood is opened.
• The vehicle has been stopped for about 3 minutes.
If vehicle-to-vehicle distance control driv ing is automatically canceled for any other
reason, there may be a malfunction in the system. Contact your Lexus dealer.

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■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.
●Actual 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 turn ed 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 assist function 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 obstructions, such as snow, ice or plastic
objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control with full-speed range is canceled if an obstruction is
detected.
■Warning messages and buzzers for dynami c radar cruise control with full-speed
range
Warning messages and buzzers are used to indicate a system malfunction or to
inform the driver of the need for caution while driving. ( P. 5 1 6 )
Grille cover
Radar sensor
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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.

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Driving
CAUTION
■To avoid inadvertent dynamic radar cruise control with full-speed range activa-
tion
Switch the cruise control off using the “ON/OFF” button when not in use.
■Situations unsuitable for dynamic radar cruise control with full-speed range
Do not use dynamic radar cruise control with full-speed range in any of the follow-
ing 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 city streets
●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
●In areas where the driver is likely to encounter pedestrians, motorcyclists, bicy-
clists, animals, stationary objects or other people/objects not detectable by the
system. ( P. 2 6 6 )
●During emergency towing

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Driving
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 your 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 the sensor or grill cover with non-genuine parts.

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Driving
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. 239) 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 7 5 )
Functions included in the LKA
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