EQUIPMENT DESCRIPTION: THIS RECALL IS FOR TRAILER TOWING WIRE HARNESS CONVERTERS INSTALLED BY DEALERS OR FOR INSTALLATION ON 1999-2000 TOYOTA TUNDRA AND TACOMA VEHICLES. THE CONNECTORS INTEGRATE THE VEHICLE’S TAIL LIGHTS, BRAKE LIGHTS, AND TURN SIGNAL LIGHTS WITH THOSE EQUIPPED ON THE TRAILER, ARE DEFECTIVE. AFFECTED PART NUMBERS ARE: PT207-34000, PT207-34002, PT207-04981, AND PT214-04985. IN THE TUNDRA VEHICLES, THE CIRCUITRY UTILIZED IN THE CONVERTER WAS INADEQUATE TO PROPERLY MANAGE VEHICLE AND/OR TRAILER-SIDE VOLTAGE SPIKES. IF THE CONVERTER IS EXPOSED TO A VOLTAGE SPIKE, IT MAY CAUSE AN ELECTRICAL SHORT OR OPEN CIRCUIT WITHIN THE CONVERTER. IN THE TACOMA VEHICLES, DUE TO DEFICIENT WATERPROOFING AND IMPROPER INSTALLATION LOCATION OF THE CONVERTER, WHICH IS MOUNTED IN THE LOWER PORTION OF THE TAILGATE CAVITY OF THE VEHICLE, AN ELECTRICAL SHORT CIRCUIT WILL OCCUR IF WATER ENTERS THE CONVERTER HOUSING.