Toyota Lexusc Owner's Handbook Manual page 500

Conventional (fixed speed) cruise control
mode
This mode allows you to cruise at a desired speed over
about 45 km/h (28 mph) with your foot off the accelerator
pedal.
Your cruising speed can be maintained up or down grades
within the limits of engine performance, although a slight speed
change may occur when driving up or down the grades. On
steeper hills, a greater speed change will occur so it is better
to drive without the cruise control.
CAUTION
D In the conventional (fixed speed) cruise control
mode, the approach warning does not activate and
no alarm will sound even if you are too close to the
vehicle ahead, as neither the presence of the vehicle
ahead nor the vehicle-to-vehicle
detected. Pay special attention to the distance
between your vehicle and the vehicle ahead. Always
confirm the setting in the display.
D Do not use the conventional (fixed speed) mode in
the following conditions, or serious injury or death
could result:
To help maintain maximum control of your vehicle,
do not use conventional cruise control mode when
using dynamic laser cruise control while driving in
heavy or varying traffic, or on slippery (rainy, icy or
snow-covered) or winding roads.
Avoid vehicle speed increasing when driving
downhill. If the vehicle speed is too fast in relation to
the preset speed in the conventional cruise control
mode, cancel the conventional cruise control mode
and then downshift the transmission to use engine
braking to slow down.
distance is
STARTING AND DRIVING
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