Here is the operation of the battery disconnect via the 2012 Greyhawk Owner's Manual.
12-VOLT BATTERY DISCONNECT
The 12-volt battery disconnect switch is
located near the entrance door. This
momentary switch controls a latching type
solenoid (located near the house batteries),
which connects or disconnects the house
batteries dependent upon the number of times
it is pushed. When engaged the battery
disconnect solenoid supplies battery power to
all accessories connected to the house 12-
volt fuse panel.
The battery disconnect feature should be
used to disconnect the motor home from
house battery power during periods of storage
or during maintenance. The solenoid must be
engaged for the 12-volt house electrical
system to operate.
Never depress the momentary battery
disconnect switch for longer than 1 second.
Depressing and holding the switch down will
disable the battery disconnect solenoid.
Should this occur the main ground cable for
the house batteries must be removed for 1
minute to re-enable the solenoid operation.
As to what I gather from that, it is a 3 way switch. short momentary contact turns power on/off to the coach. Long contact disconnects from everything.
Since I will be full-timing, I guess I really won't need to worry about the disconnect switch. Unless I'm changing out batteries. I feel that I will also be boondocking about 60% of the time. I plan to get solar going asap and figure out the 2 - 6 volt conversion.