Toyota Lexusc Owner's Handbook Manual page 506

Vehicle's height mm (in.)
"HI"
+30 (1.2)
"N"
-7.0 (0.3)
30 (19) — 50 (31)
(50)
" "HI" (high) mode
"HI" (high) mode: The vehicle's height is about 30 mm (1.2
in.) higher than the normal height.
This mode is suitable for driving on bumpy roads.
When the vehicle speed exceeds approximately 50 km/h (31
mph) or driving at the speeds of 30 km/h (19 mph) or over for
ten seconds total in "HI" mode, "N" mode is automatically
selected. Even if the vehicle speed then reduces to under 50
km/h (31 mph), the vehicle's height will not return to "HI" mode.
Vehicle speed
km/h (mph)
80 100
(62)
STARTING AND DRIVING
CAUTION
The "HI" mode should be used for severe off-road
driving conditions only. As the vehicle's center of
gravity is higher in this setting, the vehicle may become
unstable when turning abruptly, resulting in an
unexpected accident.
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