COMPLAINANT WAS TRAVELING ON INTERSTATE HIGHWAY WHEN DRIVER'S LEATHER SEAT SUDDENLY BECAME EXTREMELY HOT, CAUSING BURNS TO LOWER BACK AND BUTTOCKS. SEAT BECAME HOT DESPITE FACT THAT SWITCH CONTROLLING HEATED SEAT HAD BEEN, AND WAS STILL IN THE "OFF" POSITION. SEAT CONTINUED TO BURN REGARDLESS OF SETTING OF 3-POSITION CONTROL SWITCH. SEAT CONTINUED TO BURN DESPITE VEHICLE BEING TURNED OFF. SEAT CONTINUED TO BURN UNTIL COMPLAINANT LOCATED DRIVER'S SIDE FUSE BOX AND REMOVED FUSE MARKED FOR DRIVER'S HEATED SEAT/BCM. VEHICLE MUST CONTINUE TO BE OPERATED WITH FUSE REMOVED AS RE-INSERTION CAUSES SEAT TO AGAIN BURN REGARDLESS OF SWITCH POSITION OR VEHICLE ON/OFF. PASSENGER HEATED SEAT WAS/IS UNAFFECTED BY THE DEFECT OR REMOVAL OF FUSE. INCIDENT DATE IS APPROXIMATE. *JB