STARTED THE TRUCK WITH AUTO START TO LET IT WARM UP (OUT TEMP APPROX. 38* PLUS WIND CHILL), TURNED ON DEFROSTER IN BOTH FRONT AND REAR. WITH IN 60 SECONDS THERE WAS A LOUD BANG LIKE A GUN SHOT AND SMOKE COMING FROM REAR RIGHT PASSENGER SIDE BACK WINDOW. WHEN I GOT OUT OF TRUCK TO CHECK IT OUT THERE WAS A SMALL FLAME AT BASE OF PASSENGER SIDE BACK GLASS AND PLASTIC WAS MELTING. THE INSIDE BACK SEAT WAS WARM TO TOUCH, I WAS UNABLE TO GET SEAT FORWARD TO SEE IF THERE IS ANY INSIDE DAMAGE. THERE IS MELTED PLASTIC DOWN OUTSIDE CAB OF TRUCK. I WENT ON LINE TO (HTTP://WWW.CARPROBLEMZOO.COM/FORD/F-150/REAR-WINDOW-DEFOGGER-PROBLEMS.PHP) AND FOUND THAT THIS SITE HAD OTHERS THAT EXPERIENCED THIS SAME THING. EVEN AFTER THE TRUCK WAS OFF, THE BACK GLASS REMAINED HOT FOR ABOUT 15 MINUTES. THE GLASS IS SHATTERED AND IS HELD IN PLACE BY THE AFTER MARKET WINDOW TINTING. *TR