All of the lights on the bus worked, meaning they would come on when presented with voltage. However, some did not come on in response to the correct driver action. Others came on without any driver action. The maladies were confined to the rear, and impacted things like brake lights and turn signals. Not the items you want to malfunction on an old slow vehicle. The wiring harness on the bus is so basic that a diagram is not really needed. And therein lay the problem. When they painted the bus, they Painted over ground points, and introduced enough of an issue to make things wonky. It took a little time and some sandpaper to get things more consistent. Then everything worked until the lights were on. Turn signals, brakes, park lights, even the license plate light. I can see how this escaped the previous owner, as he admittedly never drove it much at all, and never at night. However, the shop he entrusted it to for paint had wired the rear lights backwards. Once corrected, everything worked except for the indicator lights in the speedo guage. That will be an Adventure for another day. I added some Euro lenses while I was at it, and LED bulbs to increase visibility.