Ok I tried something else that might give me an idea. I pulled the power cord and ethernet cord out of the cord block for the GPS unit on the left. Reconnected them without the whole block. Same result. But, when I left it powered up and pulled the ethernet cord out, then I got more alarms regarding the loss of GPS. I think that tells me that all of my connections are good. But maybe I have a buggered 2D sonar and a buggered SI sonar?