Windshield Wipers And Washer - Ford 1998 Windstar Owner's Manual

Controls and Features
Flashing the Lights
To flash the headlamps, pull the turn signal lever toward you
for a moment and then release it. The high beam headlamps
will flash whether the headlamps are on or off.

Windshield Wipers and Washer

Variable Interval Wipers
Your vehicle has wipers that operate at varying intervals. For
example, you can set the interval so they wipe less often in
light rain or more often in heavier rain. The wiper delays range
from about 1.5 to 20 seconds.
Variable interval wiper control
To set the interval wipers, rotate the knob at the end of the turn
signal lever to the most effective interval. The farther the knob
is from the OFF position, the more frequently the wipers
operate.
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