Marty, thanks for the idea to press Aux2 in regular operating mode. Pressing Aux 2 made the engine start running in superslow forward motion. It also caused the interior cab lights to come on. It also gave me a "screen" on the legacy controller I had never seen before, with button icons, some of which I had never seen before. However, the front headlight did not come on. I wish I had videoed what happened so I could send it to you. But the new screen that came up on Aux 2 disappeared after two cycles.
Any other ideas to get the front headlight working? I really appreciate your help so far. David