The previous owners set my truck up for towing, hitch and 7 way wiring. However I checked the 12V battery line and found it not hooked up. After crawling under it appears they attached an aftermarket harness into the existing plugs. It doesn't appear to be the factory one, luckily they didn't splice.

There is a wire coming out of the 7 way plug but I haven't traced to see how far up it goes. Since the 12V battery charge line usually needs 10ga wire I'll probably just run my own anyway, but the question I have is, will there need to be another line ran for the brake controller or do non-factory trucks have that already run? I looked up by the brakes under the dash and didn't see that little blue connector.

 

what ever the issue is dont forget pics to help the next reader.