Page 320 of 1014

3094-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
When constant speed control mode is selected, your vehicle will
maintain a set speed without controlling the vehicle-to-vehicle dis-
tance. Select this mode only when vehicle-to-vehicle distance con-
trol mode does not function 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 con-
trol mode.
(Push the lever forward and
hold for approximately 1 sec-
ond.)
Cruise control indicator will come
on.
When in constant speed control
mode, to return to vehicle-to-vehi-
cle distance control mode, push the
lever forward again and hold for
approximately 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 dis-
tance control mode.
Adjusting the speed setting:P.
299
Selecting conventional constant speed control mode
1
2
Page 322 of 1014

3114-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
Dynamic radar cruise control 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 50 km/h (30 mph).
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 dis-
tance 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 40 km/h (25 mph).
VSC is activated.
TRC is activated for a period of time.
When the VSC or TRC system is turned 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 high speed (when the wiper switch
is set to AUTO mode or the high speed wiper operation).
When snow mode is set.
If vehicle-to-vehicle distance control driving is automatically canceled for
any other reason, there may be a malfunction in the system. Contact any
authorized Lexus dealer or repairer, or another duly qualified and equipped
professional.
Page 323 of 1014

3124-5. Using the driving support system
GS450h_300h_OM_OM30D53E_(EE)
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 16 km/h (10 mph) below
the set vehicle speed.
At this time, the memorized set speed is not retained.
Vehicle speed falls below approximately 40 km/h (25 mph).
VSC is activated.
TRC is activated for a period of time.
When the VSC or TRC 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 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 and plastic objects, cannot be detected by the obstruction sensor.)
Dynamic radar cruise control is canceled 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. 841) Grille cover
Radar sensor
1
2
Page 326 of 1014

3154-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
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
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.
Assisting the driver to measure following distance
The dynamic radar cruise control 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
careless or inattentive driving, and it is not a system that can assist 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 dis-
tance 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 determine 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.
Page 327 of 1014

3164-5. Using the driving support system
GS450h_300h_OM_OM30D53E_(EE)
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 speed control and could cause an acci-
dent 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 sen-
sors from functioning correctly (fog, snow, sandstorm, heavy rain, etc.)
When an approach warning buzzer is heard often
When your vehicle is towing a trailer or during emergency towing
Page 329 of 1014
3184-5. Using the driving support system
GS450h_300h_OM_OM30D53E_(EE)
CAUTION
Handling the radar sensor
Observe the following to ensure the cruise control system can function
effectively.
Otherwise, the system may not function correctly 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 surrounding area to a strong impact.
If the sensor moves even slightly off position, the system may malfunc-
tion. If the sensor or surrounding area is subject to a strong impact, always
have the area inspected and adjusted by any authorized Lexus dealer or
repairer, or another duly qualified and equipped professional.
Do not disassemble the sensor.
Do not attach accessories or stickers to the sensor, grille cover or sur-
rounding area.
Do not modify or paint the sensor and grille cover.
Do not replace them with non-genuine parts.
Page 330 of 1014
3194-5. Using the driving support system
4
Driving
GS450h_300h_OM_OM30D53E_(EE)
Dynamic radar cruise control with full-speed
range
Dynamic radar cruise control with full-speed range supplements
conventional cruise control with a vehicle-to-vehicle distance con-
trol. In vehicle-to-vehicle distance control mode, the vehicle auto-
matically accelerates, decelerates or stops in order to maintain a set
following distance from vehicles ahead.
Vehicle-to-vehicle distance
button
Display
Set speed
Indicators
Cruise control switch
: If equipped
Summary of functions
1
2
3
4
5
Page 331 of 1014
3204-5. Using the driving support system
GS450h_300h_OM_OM30D53E_(EE)
Press the “ON/OFF” button to
activate the cruise control.
Radar cruise control indicator will
come on.
Press the button again to deactivate
the cruise control.
Accelerate or decelerate the
vehicle to the desired speed,
and push the lever down to set
the speed.
“SET” indicator will be displayed.
The vehicle speed at the moment
the lever is released becomes the
set speed.
If this is performed when vehicle
speed is less than about 50 km/h
(30 mph) and the vehicle ahead
can be detected, your vehicle will
start following the vehicle ahead of
you at a set speed of about 50 km/h
(30 mph) (vehicle-to-vehicle dis-
tance control mode only).
Setting the vehicle speed (vehicle-to-vehicle distance control
mode)
1
2