2012 Lexus GS250 radar

2584-5. Using the driving support
GS350/250_EE (OM30C36E)
Dynamic radar cruise control
Dynamic radar cruise control supplements conventional cruise con-
trol with a vehicle-to-vehicle distance control. In vehicle-to-vehicle
distance control mode, the vehicle automatically accelerates or
decelerates in order to maintain a set following distance from vehi-
cles ahead.
Vehicle-to-vehicle distance
button
Display
Set speed
Indicators
Cruise control switch

: If equipped
Summary of functions
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2594-5. Using the driving support
4
Driving
GS350/250_EE (OM30C36E)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.
Setting the vehicle speed (vehicle-to-vehicle distance control
mode)
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2634-5. Using the driving support
4
Driving
GS350/250_EE (OM30C36E)This mode employs a radar sensor to detect the presence of vehicles
up to approximately 120 m (400 ft.) ahead, determines the current
vehicle-to-vehicle following distance, and operates 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 dis-
tance control.
Example of deceleration cruising
When the vehicle ahead is driving slower than the set speed
When a vehicle is detected running ahead of you, the system automatically
decelerates your vehicle. When a greater reduction in vehicle speed is nec-
essary, the system applies the brakes. A warning tone warns you when the
system cannot decelerate sufficiently to prevent your vehicle from closing
in on the vehicle ahead.
Driving in vehicle-to-vehicle distance control mode
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2664-5. Using the driving support
GS350/250_EE (OM30C36E)
Adjusting the speed setting:
P. 2 5 5
Canceling and resuming the speed
setting: P. 2 5 5
Dynamic radar cruise control can be set when
The shift lever is in D.
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 wipers are in
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.

2674-5. Using the driving support
4
Driving
GS350/250_EE (OM30C36E)
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 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 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. 760) Grille cover
Radar sensor
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2704-5. Using the driving support
GS350/250_EE (OM30C36E)
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.

2714-5. Using the driving support
4
Driving
GS350/250_EE (OM30C36E)
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

2724-5. Using the driving support
GS350/250_EE (OM30C36E)
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 correctly detect these types of vehicles, the
approach warning (P. 264) 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-vehicle distance control may not
function correctly
Apply the brakes as necessary in the following conditions as the radar sen-
sor 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
functioning 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