It's possible that you have the same problem that I had on my new XLR 35-12--mis-routed DC wire(s) shorting out. Here's the description that I posted several months ago:
XLR35-12 DC power failure
I wanted to update folks with an issue I encountered on my 1 month old XLR 35-12. After about 1,000 miles on the new RV, we lost all DC power while camping. Of course, the slides were out at the time. We were in Cheyenne WY with the nearest FR dealer 60 miles away.
We had no DC power period. No battery, no converter power, nada. With no DC, we lost many systems including slide operation, hot water, DC lighting, stabilizer, struts to name a few. I tried to get someone to come fix it on site with no luck so I had to learn how to bring in my 3 slides manually. That was a steep learning curve with one hydraulic slide, one electric, and one Schwintek but I did it.
I troubleshot everything I could with my voltmeter (I'm pretty handy) to no avail. I finally decided the converter was bad but it bench tested good outside the RV. When installed, the converter showed an overload condition.
I hauled the RV to the nearest FR dealer for warranty repair. The dealer in Evans CO was super! His tech worked on the trailer for 6 hours troubleshooting before he found the problem. Some "genius" on the FR line routed critical DC wires between the DC bus and the fuse panel poorly. These wires (2-3 of them) were routed between the RV skin and the frame structure. After 1,000 miles of bumps, the wires chaffed and grounded to the frame, killing my DC.
I'm posting this to help others who may find similar problems. I pick up my repaired RV tomorrow after only 1 day in the shop. Many thanks to Great Outdoors RV in Evans CO!
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