mondeo 2001 petrol

[WILLWONKER]

This mondeo as run great for 10 years (Lucky i no ) had to call RAC out because getting no power to fuel pump, every thing else is fine, he was here 2 hours trying to trace the fault, he found that one wire in the multi conection block inside fuse box was dead, as a make do and to get it started he hard wired it from a 15amp fuse to the multi block inside the fuse box, once started no problems it run good so petrol pump and all else is fine, i need to get this fixed properly. my question is could this one and only fault be from my ECU ? it does seem strange just to get this one fault from the ECU if so. any help would be great thanks