Put a multi meter to it, if you dont' have one, ask around, someone should have one should know how to use it. First check for 12v dc. if you can't find voltage, check for continuity, put 1 lead to ground and put the other lead to the outside of the socket, if it beeps, then it's plugged in, if no beep, check to see if it's plugged in. It could be either or. if you need more help, PM me
