Welcome to the Forum!Oké,
I'm having that same problem.
But first let me introduce myself...
My name is Johan,coming from Gouda Holland and driving my 4th Transporter.
The one I'm driving now is a VW T6 150 hp dsg euro 6.
No 15 amp fuse on that spot.
After putting one in the foglights are burning but no curvelights.
A few months ago everything was working as it should be.
Without the fuse....
It can be de VW garage pulled this one out during service but I never took this one out.
Maybe the whole fog curve light system is driven by software.???.
Cornering lights are enabled/disabled in the BCM by "coding".
See byte 12 bit 6, here --->