Lexus RX400h2006 Owner's Manual page 460

The vehicle−to−vehicle distance is always set to long when the
ignition switch is turned on.
Select the vehicle−to−vehicle distance considering traffic
conditions. The approximate vehicle−to−vehicle distances
when driving at 88 km/h (55 mph) is shown below:
Long . . . . . . . . . . about 75 m (245 ft.)
Middle . . . . . . . . about 50 m (165 ft.)
Short . . . . . . . . . about 30 m (100 ft.)
If vehicle speeds are slower than 88 km/h (55 mph), the
distance will be shorter than that listed above.
During long downhill driving, the actual vehicle−to−vehicle
distance may be less than that selected by the driver.
STARTING AND DRIVING
(i) Braking control
Dynamic laser cruise control is not a collision avoidance
system. If the approach warning is activated, decelerate by
applying the brakes to ensure
vehicle−to−vehicle distance.
If you are nearing the vehicle ahead traveling at a higher speed
than the vehicle ahead or if engine braking cannot be applied
properly, braking control is automatically activated. At this
time, the display flashes.
Braking control operates only when the vehicle−to−vehicle
distance control mode is selected and your vehicle speed
exceeds about 40 km/h (25 mph). If the speed falls below
about 40 km/h (25 mph), braking control will cease, requiring
the manual application of brakes.
an appropriate
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