Indeed, the fuseboxes consist of a PCB with all the connections sopldered in, they break down over the years, and become dry.

99.9% of the time opening them up and re-soldering everything fixes the car

Also, check your fuse box has the same part number, on the top white bit, it will be printed in small black print.

If i were you i would repair the old one and swap it over, and see how you get on. I bet it sorts the problem out