So, I have joined the club. The right hand light lower "eyelash" is not working. New headlight is around 650 USD, Hella substitute is a bit cheaper :-( My classmate recently replaced his Treg light because of the same problem. Seems it is quite a common issue. Volksficken.The right hand DRL has partially failed on my 2015 treg.
Center part is working, the bottom edge is not.
Rang a dealer today and was told the LED not a replaceable item, so fix is a complete headlight $1400.
Seems odd that the LED has failed inside 4 years but insane that the 'fix' is complete assembly replacement.