2007 Titan Bed Power Outlet does not work. The fuse #28 by battery is good. I don/t find any power(12 volts) or Ground connection on the socket in the bed. I've checked from a known good GND with an Ohm Meter with & can find no GND. Likewise No 12 volts with a meter or test light. Is there a connector I should be checking & where would I find it?