Pontiac 2002 Montana Owner's Manual page 169

3. Press the SET button at the end of the lever and
release it.
4. Take your foot off the accelerator pedal.
Resuming a Set Speed
Suppose you set your cruise control at a desired speed
and then you apply the brake. This, of course, shuts
off the cruise control. But you don't need to reset it.
Once you're going about 25 mph (40 km/h) or more,
you can move the cruise control switch from ON to
R/A (resume/accelerate) briefly.
You'll go right back up to your chosen speed and
stay there.
If you hold the switch at R/A, the vehicle will keep
going faster until you release the switch or apply the
brake. So unless you want to go faster, don't hold the
switch at R/A.
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