I am very interested in this because now I am having almost the same problem. I wrote 2 weeks ago that the dash lights were going out intermittingly after I had opened the dash to replace the odometer gear. But they would come back on so I figured loose connection only.

Now they come on when I start the car (dash and console lights) but after about 15 seconds they all go out for the rest of the time the car is on. The only difference between what you describe and what I experience is that I leave my headlights on all the time. Have never turned them off since I bought the car 9 years ago, so I don't ever use the headlight switch.

One thing to possibly check, I will tomorrow, is to clean the fuses. Dealer told me they have experienced problems where fuses got dirty or corroded, needed cleaning, that fixed some electrical problems.