Ford Mercury Villager 1997 Owner's Manual page 80

The defroster will turn off when the ignition key is turned to the
OFF or START position.
Never use sharp instruments or abrasive window cleaners to
clean the inside of your rear window. If you do, you may damage
the wires that are bonded to the inside of the rear window, and
cause damage to the rear window defogger.
Rear Wiper and Washer
The controls for the rear wiper and washer can also be found on
the instrument panel to the right of the instrument cluster.
The rear wiper and washer controls operate with the ignition in
the ACC and ON positions.
Rear wiper and washer switch locations
To turn on the rear wiper, press the RR WIPER switch. The
wiper will operate until it is turned off. The wiper will complete
one cycle every 10 to 15 seconds. To turn off the rear wiper,
press the RR WIPER switch a second time.
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