Why not have the option for a manual night mode for the nav on the AVIC D3? This way you could just switch back and forth and would not have to rely on headlights. This seems like a big oversight IMO. My friend has a nav that never dims when he put his lights on, its suppose to and its stock. But he can always just turn it on anyway.

Whats wrong with it being black at night and white during the day??? Seems better for night vision to me

The only slight complaint I have about the night mode being automatic with the headlights is the rainy days, it makes it a little harder to see. But they have been few lately so I just deal with it. I just adjust the dimmer for that day and then readjust it later.

Solution:

For the topic creator - My guess is that the car has daytime running lights or something to that nature that interfere with the illumination option. Tap in to the ACC power wire (or just about any 12V source, really) and run the to the radio's illumination wire. You might have to install a resistor if the illumination wire is meant to use a lower voltage, I've never checked up on that. Install a toggle switch on that wire. Now you have the ability to toggle between day and night mode with the flip of a switch.

For the above poster: Install a toggle switch on the illumination wire. That way if you have to use your lights during the day, and don't want the radio to run in night mode, just6 flip the switch.