Subaru 2001 Legacy Owner's Manual page 298

Starting and operating
once. Now the desired speed is set and the vehicle will keep running
at that speed without depressing the accelerator pedal.
n To decrease the speed
1. Push the control lever downward in the "SET, COAST" direction
and hold it until the vehicle reaches the desired speed.
When the difference between the actual vehicle speed and the set
speed is less than 4 mph (6.8 km/h), the set speed can be lowered 1
mph (1.6 km/h) each time by pressing the control lever downward in
the "SET, COAST" direction quickly within a half second.
2. When the speed decreases to the desired speed, press the control
lever downward in the "SET, COAST" direction once. Now the desired
speed is set and the vehicle will keep running at that speed without
depressing the accerelator pedal.
– CONTINUED –
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