hello, on my 1991 240, I just noticed that an electrical "box" was not attached to its wires, the wiring was hanging close to the box, but unpluged. It is about 1" x 2" grey with number
89 99 76 35 44 322 12V/50Aon it.
It sits right behind the battery.
Any idea what it is, I am reluctant to just plug it in....
Thanks, Joseph