There's a little light in the green dot shifter bezel that actually attaches to the "stick" part of the shifter. Turns on to illuminate the gear your in on the bezel. Or atleast it should...mine only does it in P, R and 2
the light is attached to the moving shifter bar, and it illuminates each stop through the whole range, P R N D 2 1. I think you have to take the shifter bezel off to get to it.