Calling all electrical system sleuths

simionsen wrote:
,,, The battery boost switch doesn't do anything when pushed. I was under the impression that it should cause the isolator to open (click). So perhaps the problems is there somewhere.

You're getting close. Actually when you close the switch the isolator will close connecting the two battery banks together. For charging either when on shore power or when going down the road that isolator (aka solenoid) will close.

Now the question is what is common that is needed to close the circuit either manually with the battery boost or automatically to cross charge? Wish I knew more concerning how Winnebago wired up the circuit to provide guidance on what to check next. The theory is pretty much the same but individual application can be different between builders.