Sorry to bear bad news, but I don't think you have what you think you have!
The AUX light switch fitted by BMW is on the mirror clamp. The BMW system also needs to be coded-in by a BMW specialist (not sure you can do this with a GS-911 but someone may know better!)
see -
https://www.ukgser.com/community/threads/r1250gs-aux-lights-did-they-use-the-correct-switch.314144/
If you did have the lights fitted (BMW ones) and they were disconnected (without being coded-out) I believe that leaves a "LAMPF" message because the bike can no longer see them, and the BMW control unit thinks they have failed...
From where you are now, the best/easiest solution would probably be this one:
Had the 1300 gsa for about a month now - and straight away I missed the old christmas tree look of the 1250gsa that I traded in.
Went aux lights shopping - and whilst I love the look of motolights (bit less so the Denali d7pro), a thousand quid all in was a bit of a stretch after just paying for the bike.
Stumbled on the CoLight D09 pro - looks a lot like the motolight, has the amber ring round the outside & seperate cricuits for diffuse low beam / focussed high beam. A triple circuit light.
Bought the hex ezcan to control it all (£200) and bought the colight D09 pro lights (£115) with...
An EZCAN module to control the lights (CANBUS ready) and some decent lights (Denali or Colight).
The benefit here is that you can use them as day-riding lights at low intensity, (I use 30% intensity whenever the bike is running) but if you're riding at night, they will give you "full blast" with full beam on your bike (and light up the road ahead in a big way!)
Putting powerful lights without a dimmer is pretty antisocial and will hack off your mates too!
Using an EZCAN and decent spots will probably be cheaper than BMW genuine ones, and far more configurable (and far more powerful). IIRC the genuine BMW setup is approx £400, and then you also have the coding-in costs on top....
