Jeep 2013 Wrangler - Manual (Page 178)

Mist Feature
Push down on the wiper lever to activate a single wipe to
clear off road mist or spray from a passing vehicle. As
long as the lever is held down, the wipers will continue
to operate.
NOTE: The mist feature does not activate the washer
pump; therefore, no washer fluid will be sprayed on the
windshield. The wash function must be used in order to
spray the windshield with washer fluid.
Mist Control
176 UNDERSTANDING THE FEATURES OF YOUR VEHICLE