temperature display

On the Aux climate system, it has a little button that helps direct the ac in the back. It says that the selected mode will illuminate on the temperature control. I dont see this happening. I can hear it change but I dont see it illuminating. Everything else is so pristine that I cant help but...

The Gen2 area has numerous posts on repairing the display, but I didn't see any on the Gen1, so would like to relate my experience in repairing the display. By the way, I am an electrical/electronic technician by trade and training. I purchased a 94 Limited that had an intermittent display...