Have you tried setting it yourself on the screen on the left of the cab window? It has a button on it that says PIS. Or, after you sit down, you could press the let arrow on the keyboard and it will take you to the screen.
Oh ok then it is a bug. I think it may be something to do with having those trains on routes they weren't meant to be on. If it is still blank then it is not your fault and it is a bug.