Lexus RX 450h 2012 Owner's Manual page 241

2-4. Using other driving systems
■
Canceling and resuming the constant speed control
240
Pulling the lever towards you
cancels the constant speed
control.
The speed setting is also
canceled when the brakes are
applied.
Pushing the lever up resumes
the constant speed control.
Resuming is available when the
vehicle speed is more than
approximately 25 mph (40
km/h).