No idea, but as your query lacks input from other readers I'll have a pop.
As you are probably aware, Series LRs of most models lend themselves to the fitting of additional "features" eg. Fog Lamps, winches etc, indeed my own S2A has had various switches added during its life Reversing Lamps, Fog lights & some other non-standard bits & pieces, probably no longer required these days.
I suggest you trial & error yours with an observing onlooker & try to pin it down always assuming your panel is identical of the one you posted. Of course you could go the long way around & trace each switch to it's end component.
Sorry I can't help further but I am not familiar with the S3 but my suggestions would be the same for any Series Vehicle.
Good Luck.
Bookmarks