I have a 2002 Monaco Windsor that came with a Sony in-dash radio and Panasonic surround sound connected to many of the same speakers. I'm not sure if the TV was also connected but probably. I now have a 2012 vintage Samsung smart TV and a Yamaha natural sound AV receiver RX - v373. I have the TV and DVD player connected to the surround sound. I used the original speaker wires for both the radio and the surround sound speaker outputs . I had both working for a while but now I get an error on the surround sound to "check speaker wires". I have checked all of them and found two open speakers for which I have replaced. My meter shows no shorts in the wires. Now I'm wondering if the short might be in the surround sound itself. Is there a way to test it externally before I tear into it? I hope you can direct me to a good set of diagrams for this setup. I have some electronics background due to being an Acura master technician for about 25 years. I've been a school trained mechanic for 57 years. Of course, that shows how stupid I am cuz there was no money in it.