I don't know what type of Converter or panel you have, but on my panel there are two fuses on the battery input which if blown will exhibit what you are seeing.
On my panel, they are the topmost fuses, and there is not "blown fuse" indicator on these two fuses.
2013 Rockwood 8289WS
Mods: Central Vac, PI EMS-HW50C, 2025RV, (2) SCS225 Trojans, PD9260, Awning Remotes & LED Lights, Eliminators, External Water Filter,, Intellijacks
2008 RAM 3500 Cab&Chassis Hauler Bed, B&W Companion Hitch
All My Modifications are at this link: