WHILE WARMING UP CAR IN DRIVEWAY, I HAD TURNED ON THE SEAT HEATERS TO BOTH FRONT SEATS AND WENT INSIDE. WHEN I CAME OUT TO LEAVE ABOUT 5 MINUTES LATER, THE DRIVERS SEAT WAS SMOKING AND MELTING THE TOP OF THE SEAT CUSHION. IT WAS ON FIRE. I QUICKLY SHUT OFF THE HEAT TO THE SEAT AND SMOTHERED THE SMOKING/MELTING SEAT. *TR