wiring sweetwater

Hi All, Trying to find out what the spare wiring loom is located under the stern, port-side corner, with the female Deutsch DT connector and green wire are actually used for please? Dave Brisbane, Australia

Have the above boat. As far as I know ACC isn't being used. Looks like brown/black stripe off the switch, then I lose it in the harness. Anyone know where the other end is? Would like to do some led lights. Oh, horn stopped working too. Likely the horn or the switch? Guess my grandson over worked it :) Thanks