Originally Posted by suss6052
That's the ambient light and solar gain sensor afaik
. Its used to tell the auto lamps to turn on when it gets dark enough, as well as for interpreting the sun load when running the climate control. At least that was my understanding if you mean the little black rectangle with a cover over it near the base of the windshield in the middle.
Dang my dealer to all hecks, he told me that was the IFF antenna.