The UI fault code indicates a failure in the main control board. If you see it flashing on the screen, unplug the machine and check all wires that lead from the main control board to the interface, and connections. If something gets loose, try to fix it. Use a volt meter to check voltage: the error could have been caused by excess voltage or lack of it. Not unlikely, the main control moard and/or the interface have failed. When you have finished all that, restart your washer. If the code appears again, seek professional help.