Toyota Lexusc Owner's Handbook Manual page 494

With automatic transmission (multi-mode type) —
Even if you downshift the transmission from "D" or "5" (fifth
range) to the "4" (fourth range) in the vehicle-to-vehicle
distance control mode, engine braking will not be enabled
because this mode is not cancelled. To decrease the vehicle
speed, reset to a slower speed with the cruise control lever or
depress the brake pedal. If you use the brake pedal, cruise
control is cancelled.
(g) Resuming the preset speed
If the preset speed has been cancelled, when you push the
lever up in the "+ RES" direction while the "READY" indicator
in the instrument cluster comes on at a vehicle speed of more
than 40 km/h (25 mph), the speed set prior to cancellation will
be restored.
During follow-up cruising, if there are no vehicles ahead
because they have changed lanes, your vehicle will accelerate
gradually up to the preset speed. At this time, pushing the lever
up in the "+ RES" direction will quickly speed up your vehicle
in vehicle-to-vehicle distance control mode.
STARTING AND DRIVING
(h) Changing vehicle-to-vehicle distance
"
LONG MIDDLE
1 2
You can select one of the following vehicle-to-vehicle
distances.
1. LONG
2. MIDDLE
3. SHORT
Each time you pull the distance switch briefly toward you, the
setting changes from LONG to MIDDLE to SHORT and then
back to LONG. You can confirm the setting on the display.
Your vehicle speed changes in proportion to the speed of the
vehicle ahead, maintaining the selected distance. However, if
the vehicle ahead is slower, the selected distance will be
shorter than the designated distance.
When the vehicle-to-vehicle distance control mode is
activated or the "READY" indicator comes on, the
vehicle-to-vehicle distance setting can be changed.
SHORT
3
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