Need Help Please!!

Just to clarify, I did have low voltage across the entire trailer the other day. And you told me after that that I should use a multi meter and disconnect each connection and test everything one at a time, starting with the power source, etc. which is what I did. I decided to put the old fixtures back in for a separate reason. I had decided prior to that that I preferred the old fixtures because they were better quality. I mentioned that I replaced them because I was just trying to list everything that I did but I think maybe it threw everyone off because it sounded like that's all I did. I think it's easy to misunderstand people sometimes online, and maybe I wasn't explaining myself very well. I hope you won't feel the need to ignore my posts from here on out because it was your advice that got me through this issue and I really appreciated your help!