Ford 1999 Crown Victoria Owner's Manual page 70

Controls and features
Do not use the speed control in heavy traffic or on roads that
are winding, slippery, or unpaved.
To set a higher set speed
Press and hold SET/SET ACC/
SET ACCEL. Release the control
when the desired vehicle speed is
reached or
Press and release SET/SET ACC/
SET ACCEL. Each press will
increase the set speed by
1.6 km/h (1 mph) or
Accelerate with your accelerator
pedal. When the desired vehicle
speed is reached, press and release SET/SET ACC/SET ACCEL.
You can accelerate with the accelerator pedal at any time during speed
control usage. Releasing the accelerator pedal will return your vehicle to
the previously programmed set speed.
To set a lower set speed
Press and hold CST/COAST.
Release the control when the
desired speed is reached or
Press and release CST/COAST.
Each press will decrease the set
speed by 1.6 km/h (1 mph) or
70
RESUME
SET
ACCEL
COAST
RESUME
SET
ACCEL
COAST