I think you are missing the point... when you park an aircraft you shutdown the engines and connect up to an external power source (GPU or on board APU) then you shut down the systems on the aircraft that are not needed, say the fuel pumps, and other aux items, which most are listed in checklists, which the Boeing 767 has built in (menu) Go to the tab "Procedures" then "Shutdown" and the full list of items are listed there. If you want the shortcut then use the "Auto" function to do the checklist for you, but it is better to do them yourself so you learn what is what on the aircraft's system