Lexus GS430 User Manual page 427

Vehicle−to−vehicle distance control mode
The millimeter wave radar sensor in this system primarily
detects the reflected wave from the rear end of the vehicle
ahead of you to determine the presence of the vehicle
ahead as well as measuring the vehicle−to−vehicle
distance. The detection range of the sensor is about 120
m (400 ft.) ahead.
When the dynamic radar cruise control is on, the driving
pattern of the automatic transmission is fixed in the normal
mode, regardless of the position of the selector switch.
CAUTION
The dynamic radar cruise
collision−avoidance system and will not prevent
accidents. The dynamic radar cruise control is a vehicle
speed control device that is intended for use only on
freeways or roads where the traffic is light or moderate.
To avoid serious injury, you must use caution and be
attentive to road and traffic conditions while using
dynamic radar cruise control.
(a) Dynamic radar cruise control operations
control is not a
The dynamic radar cruise control function operates
automatically and depending on whether a vehicle is
detected ahead may change the speed of your vehicle as
follows:
STARTING AND DRIVING
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