Trying to get my rear locker working on my 2010 jk and can't seem to get the rear locker to engage with the factory switch. Opened up the diff and got the locker working by applying 12v to it. Tried checking the plug for power and not getting 12v there. Checked the fuse and it's good and theres power going to the relays, even tried other relays. Wheres the next place I should be check