I had similar issues with a 2014 recently. Took video of the screen going to keyboard mode, or not being able to select ZO letters etc. MasterCraft sent a replacement screen, put it in, all worked well for about three hours till we started jump with the boat, issues started again. Crossing the wakes caused a loose connection to act up, (as Jody said), we found the plug to the Zero off head unit, down on the foot board, had one pin (of three) not connecting properly. It looks like it could have been that way from manufacture.