found it.
The TIME on the D3 updates itself based on the GPS signal. you must plug in the GPS for the proper time to be displayed.
I thought i broke my car this morning.
the screen kept getting dim, than bright, Than dim than bright, Than dim than bright. I couldn't figure it out.
finally dawned on me. it's responding to the headlights. Dims when the headlights are on, and brightens when they're off! And since i have automatic headlights and today is particularly grey day, they kept switching on and off.
I'm finding more and more features of this thing everyday and i'm