Hey folks, I thought this would be easy to find but I can't... I had to cut off the stock trailer harness plug from my 2019 Q7 - it was ruined from lots of trips backing boats into saltwater. I have a new dual adapter (4 and 7 pin), but I don't know the function for each of the 7 wires in the stock harness, e.g. Brown is ground, etc. Does anyone have this info? TIA