Probably due to the wonderful gangrene that grows on copper wires here in the northeast--after about two months around here your wiring harness looks like the 100 year old copper roof on the county courthouse.The resistance caused by this corrosion heats the plug up to the melting point.I have seen headlight bulbs break the low beam filament and it touches the high beam one,causing them to both light up at the same time,causing high amp draw--also the "third"prong on the bulb is ground,if the filament touches that one it could act like a short curcuit--and since there is no fuses on most vehicles headlights,the headlight switch has a built in curcuit breaker--which sometimes fails to "break"and allows things like wires and plugs to get hot enough to melt.You might want to make sure the wires from the headlights that ground to the radiator support are in good shape,and clean and tight.Good luck!.Now that the days are getting shorter,I find myself under the hood of witchever vehicle I'm driving and wiggling the headlight plugs to get the ##YU&8 headlights to come on so I wont get pulled over--I'm about ready to cut the plugs off and solder the wires right to the headlight bulbs! /forums/images/graemlins/angryfire.gif /forums/images/graemlins/screwy.gif