NHTSA complaint: UNKNOWN UNKNOWN — ELECTRICAL SYSTEM
REPLACEMENT 15A MINIATURE BLADE TYPE FUSES SOLD UNDER THE BRAND "STOREHOUSE" ITEM NUMBER 92939 FAIL TO OPEN DURING AN OVER-CURRENT EVENT RESULTING IN SEVERE OVERHEATING TO THE WIRING, SMOKE AND SMALL FIRE. A 15A FUSE FROM THE ABOVE KIT WAS INSTALLED INTO THE "CIG" FUSE POSITION IN THE PASSENGER COMPARTMENT FUSE BLOCK OF A 1997 CHEVROLET CAVALIER. THE CIG FUSE POWERS THE CIGARETTE LIGHTER, ACCESSORY POWER SOCKET, DIAGNOSTIC LINK CONNECTOR, AND HORN ON THIS MODEL. A FEW DAYS LATER THE CUSTOMER COMPLAINED THAT THEY HAD ATTEMPTED TO USE THE CIGARETTE LIGHTER SOCKET AND THE PASSENGER COMPARTMENT FILLED WITH SMOKE, AND AFTERWARDS THE HORN AND CIGARETTE LIGHTER WERE INOPERATIVE.INVESTIGATION REVEALED THAT AN OVERCURRENT EVENT HAD CAUSED THE WIRE FROM THE FUSE BLOCK TO THE CIGARETTE LIGHTER SOCKET TO OVERHEAT AND IGNITE. THE WIRE MELTED THROUGH IN ONE SPOT WHICH WAS WHAT ULTIMATELY BROKE THE CIRCUIT. THE SMALL FIRE EVIDENTLY QUICKLY EXTIGUISED ITSELF AS THERE WAS LITTLE SECONDARY DAMAGE EXCEPT TO OTHER WIRES LOCATED IMMEDIATELY NEARBY THE AFFECTED CIRCUIT. THE INSTALLED 15A FUSE WHICH FAILED TO OPEN WAS RECOVERED AND SHOWS SIGNS OF HEAT TO THE CONDUCTORS BUT FAILED TO BREAK THE FUSIBLE LINK. SUBSEQUENT LABORATORY TESTING DONE BY US ON AN ANOTHER 15A FUSE FROM THE SAME BATCH FOUND THAT THE FUSE SUSTAINED A CURRENT OF 30A INDEFINITELY WITHOUT OPENING. FURTHER TESTING AT HIGHER CURRENT SHOWED THE FUSE SUSTAINED A CURRENT OF APPROXIMATELY 200A FOR APPROXIMATELY 1 SECOND BEFORE TH
National Highway Traffic Safety Administration — Office of Defects Investigation