THE VEHICLE IS A 2001 DODGE DAKOTA QUAD CAB EQUIPPED WITH A FACTORY TOWING PACKAGE. ON MARCH 12, I WAS DRIVING THE VEHICLE ON I-215 PULLING A TRAILER. I SMELLED SOMETHING BURNING, THEN THE CABIN FILLED WITH SMOKE. THE TURN SIGNALS, BRAKE LIGHT, AND EMERGENCY FLASHER CEASED OPERATING. A COMBINATION FLASHER UNIT HAD FAILED AND BURNED, WITH THE PLASTIC CASE PARTIALLY MELTED. THE HEAT HAD DAMAGED THE COMBINATION SWITCH, WHICH ALSO FAILED, AND THE PLUG INTO THE WIRING HARNESS WAS ALSO PARTIALLY MELTED. THE DODGE DEALER CHANGED THE FAILED COMPONENTS, AND THEY FAILED AGAIN, THIS TIME WITH NO TRAILER ATTACHED. THE DEALER FINALLY ATTRIBUTED THE FAILURES TO A SHORT CIRCUIT IN THE WIRING INSTALLED BY THE FACTORY WHICH CONNECTED THE FACTORY INSTALLED TRAILER SOCKET TO THE ELECTRICAL SYSTEM. I HAVE ADVISED DODGE OF THE PROBLEM, AND THEY MAINTAIN THAT THEIR WIRING WAS NOT DEFECTIVE BECAUSE THEY BELIEVE THAT THE SHORT ORIGINATED IN THE TRAILER WIRING. THEY MADE THIS DETERMINATION WITHOUT EXAMINING THE TRAILER. EVEN IF THE SHORT DID IN FACT START IN THE TRAILER, THE FACTORY DESIGNED AND INSTALLED WIRING HARNESS SHOULD HAVE PREVENTED THE SHORT FROM DESTROYING THESE VITAL SAFETY COMPONENTS. THE FREEWAY I WAS ON WHEN THE FIRE OCCURRED WAS PACKED WITH RUSH HOUR TRAFFIC, AND IT WAS EXTREMELY DIFFICULT MAKING MY WAY TO SAFETY PULLING A TRAILER WITHOUT THE USE OF THE SIGNAL LIGHTS. *JB