Thanks for the response.
I finally found the 50amp breaker hidden high inside battery compartment, but it’s a stand-alone without an external breaker (yellow flag). So not sure how one knows if it’s bad.
By the way...with all the stress & commotion, I forgot to reset the 100amp yellow flag in the battery compartment.
For the life of me, I couldn’t figure out why the Axxera radio wouldn’t power-on
Well, well. Once I discovered & reset the 100amp breaker the Axxera powered on.
So I found a replacement relay/solenoid on Amazon for $34
Although one of the comments was that you can take apart and clean the connectors as they get corroded.
So I’ll probably buy one, and clean out the current one when I return home.
https://smile.amazon.com/INTELLITEC-0100055000-Battery-Disconnect-Relay