With the truck running, using the test light I have one terminal that shows current. Would that be correct?

 

Usually the later Ford trailer connector door has the hookup schematic/ positions like the one pictured. The Trailer Tow Batt Charge is marked with a ‘+’ shown here on the lower/left of the door. The female 7 way on the trucks

depending on the door orientation and locating block position,, for this batt charge the terminal is at the 7:00 position.. If your getting 12v on the leg tested, or are unsure, to verify pull fuse 21 out, the voltage there should then be missing

 

I will check that out.
Thanks again