Backup TV Monitor Troubleshooting

Hi, In my Winnebago Sightseer 33C the backup and side view tv monitor has no picture. It is completely blank and unresponsive to any of the buttons. I suspect it may be a fuse but none of my fuses are tripped. Does anyone know if there is an additional fuse behind the dash for this monitor, or have any other idea as to why this stopped working after 3 years of use? The unit came with the RV and installed in the dash. The brand of the monitor is MobileVision. Thank you.