Take a long enough wire directly from the battery. That wire will be hot so cap or tape it till you are ready to use it. One by one remove a wire from the output of the power supply and touch the battery wire to it. See what is then powered and you can identify which circuit is which. You can the label them as to the colors of your schematic for future reference.
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles