More detail about this will go in my pre-facelift OEM RGB lighting thread... but the short-ish version is that my (our) pre-facelift BCM's are capable of at least some type of LIN bus lighting control, which is necessary for RGB lighting. I have
not figured out the LIN groups/modules yet and I am
not (yet) able to control brightness or color from the Infotainment screen.
As for progress, tonight I was able to get an RGB module to light up via LIN bus control (the light always has 12V/ground) and that's a step in the right direction. It fades on when the doors are unlocked and fades off when the doors are locked, which is also good. As I'm typing this it occurs to me that most of my "testing" was done with the driver door open. There is an adaptation for brightness with door open so it's possible that was overriding any brightness adjustment I tried via the infotainment slider. However, I don't think having the door open explains my not being able to change color.
And ignore my footwell lights in this picture. They are DeAutoKey RGB footwells (the type that you change with the little remote) and are wired to a BCM light channel, as per OEM non-RGB footwell installation. I have always had them set to red. It is just coincidence that the ambient light infotainment screen is set to Red.
And that which we care about as usual, pics...