My vehicles:
2010 Golf GTD
2013 Passat Alltrack
i found this forum when researching problems I was having with the dealer fitted towbar wiring. I have since found out that the dealers did not tell me about the need for the LED modifier adapter!!! This despite me taking the vehicle back 3 times (with the trailer). I live 100km from the dealer and each time they've had the Passat all day!!
hopefully I will get some resolution.