The 12VDC FUSE PANELS are PC TYPE CIRCUIT BOARDS with all of the components sockets etc soldered on them.
They can come unsoldered but that would be rare. Your problem is most likey where the screw connection is for the circuit wire that terminates on the board.
You need to remove the cover you are showing with your screw driver where you can see the screw down connections for the circuit wiring. Those connections can work loose real easy... They probably was not installed to tork spec at the factory.
Provide the model number of the distribution panel and perhaps you can find a photo of the exact 12VDC circuit board on-line to show how the external wires connect to it..
Be careful with the distribution panel as both 120VAC an 12VC wiring exists in close vicinity here...

Typical 12VDC Fuse Panel Circuit board...
Roy Ken