I think we're talking about two separate issues - mine starts when the car has only been on for a few minutes. I have experienced the shutoff when the signal is red, yellow, white...no consistency.

My issue is when the nav system shuts off completely - I see the "Hybrid" logo and it starts itself up again. Sometimes the screen goes black, sometimes white, sometimes gibberish on the screen in all sorts of colors, and occasionally there are green, blue, white & black lines. That's my favorite.