Toyota LEXUS LS430 2005 Manual page 368

D The approach warning may not turn on even if the
vehicle drives closer to the vehicle ahead in the
following conditions:
D Your vehicle and the vehicle ahead are cruising at
almost the same speed.
D The vehicle ahead is cruising at a faster speed than
yours. (The distance between the vehicles will
become longer.)
D Pay special attention to the very slow vehicle at the
end of the line in heavy traffic or at the tollgate.
D Immediately after the speed setting
D The accelerator pedal is depressed or immediately
after the release of the accelerator pedal
STARTING AND DRIVING
(g) Millimeter wave radar sensor
(Vehicles with dynamic radar cruise
control)
31L359a
" 1 Millimeter wave grille cover
2 Millimeter wave radar sensor
The millimeter wave radar sensor is used for
vehicle−to−vehicle distance control cruising. When the
millimeter wave radar sensor is disabled for some reason,
the warning message appears on the multi−information
display. For details, see "Vehicle−to−vehicle distance
control mode failure warning" on page 352.
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