I purchased a F10 528i about 1 year ago, for the first 3 months I was searching for a suitable ambient door lighting door kit. I had been in other cars with the ambient lighting, these had white door cards so the lighting was evident. I checked and realised that I did have ambient lighting installed but it was so dark it was not possible to see it against the black door card. I did a bit of research and found this place in Germany. Having ordered replacement LED's the ambient lighting is now much brighter and noticeable. The website is in German but Google translate changes it to English easily. Good Luck.
https://www.benzinfabrik.com/de/led...-ambientebeleuchtung-fuer-bmw-standing?c=7432
https://www.benzinfabrik.com/de/led...-ambientebeleuchtung-fuer-bmw-standing?c=7432
