When the fixture first powers up, the screen should still come on. Its is after about 30s of non use that the screen powers down. Also, as soon as you hit a button on the fixture, the screen should come on again.
The screen itself doesn't have a fuse that I am aware of. I am also not sure if you can purchase just the screen and install yourself or have to send it in. That would be a question for service. I would recommend calling them about it. They might have another suggestion as well to get it working, might be something simple like a loose connection.