good idea to check the a-c clutch relay. I know that on a toyota camry, you can just switch the horn relay to “fix” a bad a-c clutch relay. when was the last time you changed the cabin air filter? I just fixed the a-c on my 1995 volvo by putting in a new cabin filter!
you found a bad wire, good job. I would still do a voltage drop test of the pos. and neg. side under load. if the drop is more than 0.2V, you have a bad wire. cables should be checked first when evaluating alt. problems
if your car would run, you could do a voltage drop test on the pos. cable. google “voltage drop” to read how. I agree with the first poster: replace the pos. cable. if that fixes it, do a voltage drop on the ground cable.