Zantrex 2000 - side shore plug not working

[Jspolson]

Hi. Just bought my first airstream, that being a 2018 International 27fb. The last user installed a Zantrex x 2000. I’ve been going crazy trying to get shore power working, but then decided to plug the trailer into the house using the front plug rather than the side plug and I had instant power. From what I can find on line, is there a transfer switch somewhere? Or does the Zantrex only use one source, and the using the side plug is no longer an option.

Thanks for any help, I’m pretty green on this stuff.

[Hans627]

Is there any way to contact the previous owner? FWIW I think I would start there.