I have a same situation as Darius. Triple beam lights. The grey round plastic cover, once removed is to replace the Halogen 9005 bulb. This bulb is used in the most inside portion of the headlamp. This is for the daytime running lights and highbeam.
I cannot find where to replace the DS4 bulbs. There is no other opening.
The LExus diagrams are for the non triple beam lights where behind the grey plastic cover is the DS4.
Any thoughts?