Thank you so much for posting those documents. I really appreciate your taking the time to do so. With the wiring diagram in hand, I once again remove the dash face plate to compare the wires to the diagram. As I did before, I also unplugged the two plastic pigtail connectors that connect the wire to the controller. I examined the wiring for any problems but did not find any. I then plugged the two connectors back together -- AND ALL OF THE JACKS AND LEDs ON THE PANEL ARE WORKING PROPERLY AGAIN!
Apparently, there was a bad connection somewhere right behind the controller in the dash, perhaps in one of the plugs themselves? I examined and re-examined every wire in the area, but could not identify or isolate the problem wire(s) or connection(s). I wish I could identify the problem area more specifically for you, but at least in my case I have been able to determine that the problem was somewhere in the wiring in the dash, immediately behind the control panel. Given that your system and symptoms appear to be identical to mine, you may want to focus your troubleshooting to that immediate area, rather than somewhere else in the system. Good luck, and again, thank you for your assistance.