if youhave a sliding rear window you do not have a rear defroster, to my knowledge, both was not an option, it was one or the other. the button works both the mirrors and the rear defrost if you do have both, orjust the mirrors if you dont.
COMBAT WOUNDED VETERAN
-2015 Ram 1500 Laramie Crew Cab 4x4. Lifted, Modded, Attitude.
2002 Lexus ES300. My Daily.
2014 Civic EX. Wifey
2008 Corvette Pace Car Convertible. #325/500