After a few months (I took delivery of mine in mid November), the lights no longer fog. It could be the weather but I don't think it is as it's pretty much the same as it was in November. I'm hoping that means the water vapour that was trapped inside has has escaped and I'll never see fog again.Hi Mercnut, I agree with you. paying so much money for a high end car and does not expect the LED light to fog up. and is totally embarrassing in the car park when a same GLC park next to mine and his light are clear. so the fogged up has been gone for couple of days now (thank god) but sometime on a wet day or after we wash the car it appear again. Contact mercedes and they've ask us to bring it in for them to see.