No longer charging found broken wiring

Earlier models had a 1 wire connector of different shape/color with a fusible link inline by the bulkhead. Later models got that round white connector at the same fusible link and more than that 1 location. I don't think they all had a fusible link inline. Just a simple easy way to isolate a system or circuit.
I was told that while those other builders used self powered test equipment placed along their assembly lines, the CDP builders used the vehicles live amp gauge as the indicator as they plugged in various systems/circuits.
Plug something in and amp gauge went wonky, unplug it, flag it and let it move on. Don't stop the line to dianose a bad alternator, whatever. It will be corrected later.