Buick 2011 Lucerne Owner's Manual page 165

If the cruise control system is already activated,
Press and hold the +RES button on the steering
wheel until the desired speed is reached, then
release it.
To increase vehicle speed in small increments,
press the +RES button. Each time this is done, the
vehicle goes about 1.6 km/h (1 mph) faster.
If the cruise control system is already activated,
Press and hold the SET button on the steering
wheel until the lower speed desired is reached,
then release it.
To slow down in small amounts, press the SET
button briefly. Each time this is done, the vehicle
goes about 1.6 km/h (1 mph) slower.
Use the accelerator pedal to increase vehicle speed.
When you take your foot off the pedal, the vehicle will
slow down to the cruise speed you set earlier.
How well the cruise control will work on hills depends
upon the vehicle speed, load and the steepness of the
hills. When going up steep hills, you might have to step
on the accelerator pedal to maintain your speed. When
going downhill, you might have to brake or shift to a
lower gear to keep your speed down. If the brakes are
applied the cruise control will turn off.
There are three ways to end cruise control:
To disengage cruise control, step lightly on the
brake pedal, or
Press the button on the steering wheel.
To turn off the cruise control, press the
on the steering wheel.
The cruise control set speed memory is erased from
memory by pressing or if the ignition is turned off.
button
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