last 2 months, live S FL, USA - colder weather days especially. In a.m., Nav Panel blank, no control of a/c-heat,radio, etc. Depending on how cool, screen comes on 1/2 hr later, everything ok. During day, car sits, start, blank screen, 5 min later, on. (But if car sits in sun, never a problem). In Sept and before, no prob. Not sure it's weather related? (affecting some component). Car sits in sun, no problem. 2005 S model, only has 70K, is in excellent shape.