Which gets back to the question of WHY this particular damage occured. Popular perception on most likely problem is useful when normal diagnoses is exhausted. In the other current thread on same topic (title "fusible link") the problem ended up being that that the alternator failed. So, all the power was being supplied by the battery. Knowing the specifics people were able to help the owner troubleshoot and find the root problems.


Once we know which wire(s) or connections got hot enough to melt, it will be possible to narrow the reasons as to "why this happened".
Even though the wires may have been repaired, altered or modified, it should be possible to figure out what happened.