I have a 2018 thor vegas and the 7 pin hitch connection was installed and some of the wiring was pre-done. However, the power and another wire was not connected to the hitch. See below:
http://www.thorforums.com/forums/f9/...8-a-12786.html
What i did was not totally correct so the trailer company re-wired the power wire directly to the battery and used a heavier gage wire.