Thanks, I do have the Magnadyne! Here is a picture of the switch in the stairwell
I haven't touched it since the PDI. So it's been in the ON position. Tomorrow I'll try it in the OFF position and see if that works. But I'm thinking, from your explanations, that it won't. It should have the new wiring - the tv is 12v which surprised me. Does the coach need to be unplugged for the batteries to kick in? I already know the radio has issues as the PDI tech has trouble and went ahead and ordered a new one but some functions work and some don't. And I spoke too soon about the surround sound - I found a huge speaker in a cabinet that wasn't on but I know that JamesR has a topic about this already so I will go read that. I will also find the Magnadyne thread that GerryM mentioned.
Again, thank you all for your help! I am stumbling through this thanks to you all.