Schematic for Outside Lighting

[Weavejo1]

Schematic for how I wired my outside lights. I have two in the back above the dropdown door and two on each side up high in the front and back. I wanted the lights to function in three different modes.

1) Manually switched on and off individually when the trailer is free standing and powered by the trailer internal 12v supply.
2) Manually switched on and off individually when the trailer is hooked to tow vehicle and using power from tow vehicle. (trailer internal 12v supply turned off at battery)
3) Set to turn on and off automatically when the the tow vehicle is placed in reverse, using vehicle power.