Ford 1998 Windstar Owner's Manual page 104

Indicator Light (If equipped)
Lights when either the SET ACCEL or RESUME switches are
pressed and remains lit until it is either disengaged or turned
off.
Setting the Autolamp Delay System (If equipped)
Autolamp delay allows the headlamps to remain on after the
vehicle is parked and the ignition is turned off. The slide knob
on the bottom of the mirror controls whether Autolamp is ON
or OFF as well as the length of the delay. The delay can be
adjusted from 1 second (far left position, but not OFF) up to 3
minutes (far right position). A green indicator on the lamp lets
you know that the headlamps are being controlled by the
Autolamp system.
The autolamp system
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