12v Constant on Trailer Plug?

[ScubaSteve]

Its a long story regarding the grand incompetence of multiple parties, but suffice it to say, I had to replace the main chassis harness in my truck leading from the bulkhead connector in the driver's fender well to the rear of the truck.

That being said I found the replacement harness to be defective in that the 12v Aux pin and the parking lamp pin in the 7 pin trailer plug connection had been placed incorrectly (I had to swap the two wires). Now that I have corrected that, my concern is that the 12v Aux pin has a constant 12v feed, even with the truck off. So with that, might I ask if someone would be willing to go test the number 4 pin in the attached diagram and see if it has a 12v feed with the truck off? I am finding conflicting info as to whether it should be switched or if it should be constant.

Thanks in advance!

[EasyDoesIt]

Confirmed, 12v power at pin 4 when vehicle is off.

[Mule]

yeah, that one's always-on.
Fords put that pin on a relay so it's only on with ignition.

I ended up putting a switch in my trailer to connect/disconnect that pin to the trailer. Lets me isolate the truck so I don't kill its battery with the furnace/lights, but I can still charge the batt on the way there or back.

[ScubaSteve]

Sweet. Thanks a lot!

[RustyPW]

On my motorhome. It's only powered with the key on.