The Truma display/control panel is fixed. I took it to Auer’s RV Service Center in Georgetown, TX. They are a certified Truma Partner. The technician pulled the display panel. He did not find anything wrong but disconnected all the wires, checked the voltages and reconnected them. The panel lit up. He thought it might have been a loose connection in a Wago connector.
Thanks for your guys thoughts. I was afraid I might mess it up worse.