All electronic instrument panels were a nightmare in the mid 80's to the mid 90's, one loose connection, dirty switch contacts, cold solder joint, driver would be blind. Even the Lexus was a major problem, used a back lighted LCD screen that would turn black permanently in subzero weather. Took them long enough to go back to analog.
Driver's information display can have this problem that brings about questions, what are they using for back lighting. All I can find out about it in the shop manual is this.
Is a 380 buck part and takes a half an hour to replace it. More than likely since all the information was lost and it came back was, has to be a loose connection someplace. But the same was true of all electronic dashes, no circuits either, had to remove and study them, very typical was to find a cold solder joint someplace.
On a GM S-10 using a high voltage florescent display the idiot that designed the inverter went by the transistor manual for full power output of the driver transistors at 25*C, what an idiot, transistors didn't even have a heat sink. Installed larger transistors mount to the steel for a heat sink that solved this problem forever. But GM was making a small fortune selling new instrument panels that also wouldn't last very long.
With the DIC, only way to learn this is to take it apart, but if it does go out, trying slapping the dash hard.
Ha, my youngest son had a 90 T-Bird with a dash like this.
Would be a nightmare to remove this dash, but one could slap on the top of the IP, it would work for the next couple of months. And kept on doing this for the next 130K miles until he finally got rid of it.
