Replaced them with some led pods, looked and the fsm, it says its the ambient air sensor for temp/compass. Think that's for the display on the rear view mirror but I don't have it on mine so I'm trying to see if it ever was connected to anything
Got a better look at the connector wires and one is purple and yellow, the other is purple and blue
'06 FSM
VT/YL & VT/ LB is for the mirror sensor.