I noticed that the hour meter was not working, so i thought I'de start by checking the plugin........i got a 12v reading on one wire and concluded that if i had power to it, that i should get some kind of reading ......the screen is just blank........Is it wiring or just a dead gage??......I'm leaning toward..dead gage??........thanks in advance.......no hurry.......just trying to find something else to tear into