TURNED DRIVERS SEAT HEAT FEATURE ON, AFTER A FEW MINUTES I SMELLED BURNING. MERCEDES JUST REPAIRED A/C (3 VISITS) SO TURNED OFF THE A/C. NEXT THINK I KNOW SMOKE IS COMING FROM DRIVERS SEAT, MY 3YR OLD RIDING IN HER CAR SEAT "INSTALLED" BEHIND ME. HEATER IN DRIVERS SEAT WAS BURNING, WITH THE AIR NO LONGER BLOWING, SMOKE WAS NOW VISIBLE. I HAD TO CROSS 3 LANES OF TRAFFIC TO PULL OVER. THE "FIRE" BURNED A HOLE THROUGH THE LEATHER SEAT TO MY JEANS LEAVING ME A SLIGHT BURN. CAR TOWED TO MERCEDES. *TR