Bruce,
As I best recall, the inverter-powered outlets are primarily the kitchen, bathroom, and bedroom outlets--seems like the outside outlet is also included if I remember correctly. Could always double-check by firing up your inverter (off of battery power only), and try various outlets to verify which are powered.
Phoenix calls the "white switch" a "trickle charger", and it's purpose is to possibly bail you out if you find yourself somewhere with a dead chassis (Ford) battery that won't crank over your engine, but hot house batteries. Ideally, you need to be able to plug in to external power or start your generator to raise the house battery voltage as much as possible. Then you turn the ignition key forward to ON (but not START) position, and press and hold the white switch for a few seconds. That pulls in a relay that connects the hot house batteries with the dead chassis battery and allows them to gradually charge up the dead battery. After some time (hour or so), you should be able to crank the engine.
Phoenix just posted a copy of their newly-produced "Phoenix USA RV Owners Manual" a week or so ago on the Owner Resources page of the website. Here's the link:
https://www.phoenixusarv.com/view-Phoenix-USA-RV--owners-manuals. It covers some of the general guidance and questions regarding PCs--it might be of some help if you haven't already seen it (description of the "white switch" is on page 33). There are many component manuals on the same resource page which will cover many of the components used in your unit. Collectively, it's a pretty helpful resource page for PC owners.
All the best, Mike
