WAS DRIVING MY 2006 CHEVROLET SILVERADO 2500HD AND TURNED ON THE AIR CONDITIONER. I BEGAN TO SMELL AN ODOR SIMILAR TO TRASH BURNING. I TURNED OFF THE AC AND TURNED ON JUST THE AIR FAN AT WHICH TIME THE TRUCK CAB FILLED WITH SMOKE. I WAS ABLE TO PULL OFF THE SIDE OF THE ROAD AND CONTACTED THE FIRE DEPARTMENT. THE FAN CONTINUED TO FILL THE CAB WITH SMOKE EVEN THOUGH THE IGNITION WAS OFF AND THE KEYS WERE REMOVED. THE INCIDENT DID NOT STOP UNTIL THE FD DISCONNECTED THE BATTERIES FROM THE TRUCK. THE VEHICLE WAS TOWED TO A CHEVROLET DEALER AND THE PROBLEM WAS DIAGNOSED AS A SHORT IN AIR CONDITIONER BLOWER WIRING HARNESS WHICH RESULTED IN DAMAGE TO THE RELAY, THEY CHECKED WITH THE MANUFACTURER TO AUTHORIZE REPAIR UNDER AN EXTENDED WARRANTY AND TOLD ME IT IS NOT COVERED AS IT IS AN ELECTRICAL MALFUNCTION. *TR