Battery & electrical questions

Odds are, the connection between the chassis and coach systems is made with a electric solenoid/relay. Sometimes diodes are used but I do know Winnebago uses relays, and so do some other manufacturers. It is open, separating the systems until you start the engine, then a special key on circuit energizes the solenoid. If you have a "boost" switch that allows you to jump start the chassis engine from the house/coach batteries, you can depress it and listen for the solenoid. That is the reason for using the solenoid, it can carry the heavy starting loads that a diode would not be able to, and its probably cheaper also.

Charles