What is this "light" for in the the tail light?
 

Hello all,
Been a long time Lexus owner, both 2005 LX470 and 2003 GS430. I am getting ready to do some modifications - HID, and other lighting updates, and I cannot figure out what this light is for.

It is not part of the turn signal, nor the backup lights (those are on either side of the license plate). For the life of me I cannot figure out what they are for, or if there is even a light in there.

1) Does anyone know what is going on there?
2) Is the same spot on the 06+ style LED headlights also 'void' (I am thinking about switching to them)
3) I wonder if I could install rear fog lights (AKA Back off my @$$ bright lights - I don't get thick fog here)


https://cimg5.ibsrv.net/gimg/www.clu...f826448f94.jpg


NOTE: if for any reason the photo does not show, or is removed over time - this is the 'white' inner light on the tailgate lights, not the outer turn signal light.

Looks strictly cosmetic to me.

I believe these were used as backup lights in the older models. E.g. 2000