There is a 3amp automotive-style fuse, but it's on the Intellitec control panel that is installed in your 120v breaker panel.
Agreed with ChasA, need more info. Do you mean the display panel has gone dark? If so, try removing the bezel around it, remove the screws that hold it in place, and GENTLY pull it away from the wall. There is a cable that runs from the display to the main panel in the breakers. It has a habit of coming loose.
If that's not it, the manual has an extensive diagnostic section.
Have you checked the obvious? Shore power good, all breakers working, power throughout the coach etc? Be sure to kill power before going into the 120v breaker panel.