What wire from the battery powers the fuse box under the hood on a 1992 Dodge Dakota 3.9

 

OK. Sorry about the mistake earlier. The picture shows the 2 wires branching off the + bat cable coming back to the fuse box on my 94 3.9. I think they join the harness under there but I could not see.
Look over the FAQ page there is at the top of it a section "Truck will not start." it discusses a common problem that happens to all daks of any year or motor. Could hopefully be just that simple for you. The main harness seems like it comes out of the engine fuse box to the front then bends around under it heading back to the firewall.

For some reason the manage attachments function won't let me upload the photo.
So if you look at the + bat terminal the wires come off it and go into a corrugated plastic cover. Below it about 10 inches two wires come out if it going towards the fuse box.
Edit- The rest of the wires coming out of that plastic cover go to a ground on the pwr steering pump mount and the other one goes down to the starter. I think one of the two that come over to the harness under the fuse box are probably the power source that feeds into the harness that goes across the firewall to the pdc.