I WAS DRIVING MY VEHICLE ON THE HIGHWAY GOING APPROXIMATELY 70MPH. MY SEAT HEATER HAD BEEN ON FOR ABOUT 10-15 MINUTES WHEN MY PASSENGER AND I BEGAN TO SMELL A SWEET, SMOKEY ODOR. THE SMOKE WAS NOT VISIBLE AT THE TIME, BUT OVER THE NEXT 5-10 MINUTES THE SMELL BECAME MORE INTENSE AND THERE WAS SMOKE VISIBLE INSIDE THE CAR. MY PASSENGER NOTICED THICK SMOKE COMING UP FROM THE BACK OF MY SEAT, CAUSING ME TO JUMP FORWARD AND SWERVE THE CAR SLIGHTLY. I IMMEDIATELY TURNED OFF THE SEAT HEATER AND PULLED OVER TO THE SIDE OF THE HIGHWAY. UPON EXAMINING THE SEAT, I FOUND THE SEAT HEATER HAD BURNED A HOLE AT BASE OF THE LOWER BACK WHERE THE UPPER SEAT MEETS THE LOWER SEAT CUSION (AS SEEN IN THE ATTACHED PHOTO). I TURNED OFF THE SEAT HEATER AND HAVE NOT USED IT SINCE. I AM CONCERNED AROUND THE SAFETY OF THIS FEATURE AND UPON SPEAKING TO A VW REPRESENTATIVE, THEY STATED I WOULD NEED TO PURCHASE A NEW SEAT AND HAVE THEM REPLACE IT AT FULL COST.