Strange Problem In 2008 Sienna, Climate Control/Nav/DVD Options

[kbmeier]

I have a strange, intermittent problem.

Every couple of days, the display in the climate control section goes blank, except for the passenger-side airbag indicator, if there is a passenger. When this display, which has the clock, the automatic temperature settings, the fan speed indicator, the climate-control mode and the sonar display, goes dark, the contols still seem to work. That is the fan still runs, its speed changes with the buttons, the sonar still goes off when you are close to something, etc. Whenever the display goes dark, the navigation system/radio will stay on even when the key removed from the ignition, everybody out of the car, and the doors locked.
If I start the car while the nav display is still on, the climate control screen will still be dark.

The car has, so far, always reset itself eventually. The nav system will continue to stay on for at least 15-20 minutes after the car has been shut off, I've seen it stay on for more than 30. I can't pin down exactly how long it stays on, but for a long time.

It looks like this happens when the car runs for a while, then it is shut off for a short period, and then started up again, but I'm not sure that it never fails when the car isn't shut off.

In this car, normally, when the key is moved to the lock position, the nav system and the DVD entertainment system will shut down.