Was changing my oil for the second time since I bought this car, and noticed this little guy just sorta hanging out beside the filter, no wire in sight with a broken off end, but the ring terminal is still screwed into it. Took it out, cleaned it up and figured I would ask what the he!! it is. Here are some pictures of it all cleaned off, has 12v (volt I'm guessing,that pretty simple) and some other stuff stamped onto it. I figure it has something to do with the oil? Here is where it screws into.