What is the wire color for running lights on a 4-pin harness?

[NHarris]

Sorry if I didn't search enough, but I'm building a tire rack for my Explorer and I have to relocate my license plate. The way the tire and rack will sit will block off the view of the license plate.
So I figure by just getting a 4-pin harness, plugging it in, and running the correct wires for running lights up to where i mount the plate, I should be able to have a light for my license plate whenever I turn on my lights.
I know that on a 7 pin connector Brown usually is running lights, but on a 4-pin what is the wire color for running lights?

If you think this is a bad idea let me know.

Thanks in advance,
Nate

 

[MountaineerGreen]

Brown wire should be the same, I don't think the colors change between the rv style and the 4 flat. The white should be the ground, I'd use that, don't rely on the ground through your tire carrier. Should work just fine. Post pictures when you get it done.

 

[NHarris]

Brown wire should be the same, I don't think the colors change between the rv style and the 4 flat. The white should be the ground, I'd use that, don't rely on the ground through your tire carrier. Should work just fine. Post pictures when you get it done.

Thanks. I checked the wires at night so the brown appeared to be black and that's what confused me. Figured I may as well ask.