The cable harness in question runs from the fuse box under hood through firewall to the passenger side foot area. At this point it connects to another harness that connects to various items at the rear of the vehicle. One circuit in particular the rear window defogger is burning wiring and socket and plug of the two wiring harness. Either the wiring or connectors burned apart without the circuit fuse blowing. The circuit has a 40amp fuse. The wiring harness for this circuit is 12 Garage. I can't find any manufacturer who recommends using 12 gauge wire on a 40 Amp circuit. This isn't even close to being correct. This is so agreegessly out of specification it would appear GM knew they had an issue with the circuit and fixed it By over fusing the circuit. This same issue on multiple models over several years.