Dead battery salvation

My dead battery salvation was to crank the generator and then the engine started. Now that was in a Class A, big engine and big generator 10 kw but I  have to wonder if that might have any influence on the new RV since there are some
similarities .... Guess I may find out one of these days. I am not a mechanic so no telling in my head what is connected to what ever.  Patricia

Need to check the set up. The battery surely should charge when plugged into shore power. See if the switch is on. There is a switch near the door.. there is a square white thing with red light... its gotta be on for all to work in sync. Our unit is 16 too.. should not be too different. If not working right something not properly ON.
Hope you find out. Not good to be out of power at start time. regards  Patricia

P S  I found out about the white face with the red button when Mr turned it off for some odd reason.
Sometimes knowing it all is a figment of imagination.

You guys can tell me if this is a good idea, or not to keep engine battery charged. See picture below. I used a "add a circuit" device to connect the house batteries to the engine battery.  It's a trickle charge setup that has a 5 amp fuse in series with a 10 amp blocking diode.  The blocking diode is to prevent the house batteries from draining the engine battery.  Been using for a month now, and no problems so far.  Now this also solves playing dash radio without killing engine battery.

So what your thoughts a d feedback?

Know what you mean about dash radio. Was very surprised to find no way to play our radio set up (Sirius) without the engine key on... in old unit we had a 12v radio switch on the dash and flip the switch for full off of radio camera and GPS. No such animal on this one.. everything seems to be connected to the key switch. Have to wonder if that is a potential for an overload. It is not a good first class set up in any event. I have seen connectors for the radio unit... so  this one missed the mark. I may be transporting my shop Sirius radio so it can be on when TV is non functioning on remote locations. I guess we now can be qualified as "Field Engineers"  and next thing we may be growing corn. Got tools... Look out. Patricia