Whoa, not good! First thought - the cover is held down against the plug by the pressure of a spring. Is the spring still there, and is it springy? Another thing - does the cover open upward? It should. If the socket is mounted upside down, you'll have the problem you describe.
If the above isn't helpful, it sounds like the plastic clip / retainer parts have gotten worn down and rounded, so they no longer latch. When you unplug the plug, you do lift the cover, right, and not just yank the plug out? If the parts are rounded, you might be able to reform them with a file, but I'm not sure how long that would last.
'Nuther silly question - I'm presuming that you have plenty of slack in the trailer's cable, right? If you turn a sharp corner and the plug pulls out, it will rapidly wear down the latch parts.
Rather than wiring the plug into the outlet, perhaps you could wire the cover down so that the remaining edge of the latch holds tight. And rather than wiring it, which is a pain, a wide rubber band cut from a bicyle inner tube might be easier to deal with. But both of these sound pretty rinky-dink. A new plug or outlet (you'll need to examine it to determine which one is worn down) may be the only good answer.
Bill
|