2013 Lexus GS450h cruise control

GS450h_U (OM30D01U)
2454-5. Using the driving support systems
4
Driving
■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.
●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 turned 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 assistance control 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 ob structions, such as snow, ice and plastic
objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is cance led if an obstruction is detected.
■Warning messages and buzzers for dynamic radar cruise control
Warning messages and buzzers are used to indicate a system malfunction or to
inform the driver of the need for caution while driving. ( P. 7 2 3 )
Grille cover
Radar sensor
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2

GS450h_U (OM30D01U)
2474-5. Using the driving support systems
4
Driving
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.

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
CAUTION
■To avoid inadvertent cruise control activation
Switch the cruise control off using the “ON/OFF” button when not in use.
■Situations unsuitable for dynamic radar cruise control
Do not use dynamic radar cruise control in any of the following 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 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
●During emergency towing

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
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 a 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 them with non-genuine parts.

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GS450h_U (OM30D01U)
4-5. Using the driving support systems
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. 236) 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 5 6 )
Functions included in the LKA
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GS450h_U (OM30D01U)
4-5. Using the driving support systems
■Lane departure warning function
●When the vehicle speed is approximately 30 mph (48 km/h) or
more
●When the lane width is more than approximately 9.1 ft. (2.8 m)
●When driving on a straight road or through a curve with a radius of
more than approximately 394 ft. (120 m)
■Lane keeping assist function
●When the vehicle speed is between approximately 45 and 112 mph
(72 and 180 km/h)
●When the vehicle-to-vehicle distance mode of the radar cruise
control is on, and the set vehicle speed is approximately 45 mph (72
km/h) or more (the function will not operate when the radar cruise
control is in set speed mode)
●When the lane width is between ap proximately 9.1 and 13.1 ft.
(2.8 and 4.0 m)
●When driving on a straight road or through a curve with a radius of
more than approximately 755 ft. (230 m)
Operating conditions for each function

GS450h_U (OM30D01U)
2554-5. Using the driving support systems
4
Driving
When the LKA system is on, the lane line display and steering wheel dis-
play are shown.Lane keeping assist function
operation indication
Steering wheel displayed:
Indicates that the function is currently
operating. (If the lane departure warn-
ing operates at this time, the steering
wheel flashes orange.)
Steering wheel not displayed:
Indicates that the function is not cur-
rently operating. (When the lane
keeping assist function is canceled,
the buzzer will beep twice.)
Dynamic radar cruise control dis-
play
Lane departure warning function
indication (when the inside of the
white line is white):
The function has recognized lane
markers. (If the lane departure warn-
ing operates at this time, the lines flash
orange.)
Lane departure warning function
indication (when the inside of the
white line is black):
A lane marker is not recognized by
the system, or the LKA system func-
tions are temporarily canceled.
Indication on the multi-information display
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7237-2. Steps to take in an emergency
GS450h_U (OM30D01U)
7
When trouble arises
A buzzer sounds and a warning message is shown on the multi-informa-
tion display. Failure to investigate the cause of the following warnings may
lead to the system operating abnorma lly and possibly cause an accident.
Have the vehicle inspected by your Lexus dealer.
Have the vehicle inspected immediately.
Wa r n i n g m e s s a g eDetails
Indicates a malfunction in the pre-collision system
Indicates a malfunction in the intuitive parking assist The malfunctioning assist-sensor is flashing.
Indicates a malfunction in the dynamic radar cruise
control system (if equipped) or the cruise control sys-
tem Press the “ON/OFF” button once to deactivate the
system, and then press the button again to reacti-
vate the system.
(Flashes)
(If equipped)
(If equipped)