What the,,,,,,,,,,,,only half the electric works. Checked the breakers, electric panel, transfer switch, all ok. Everything runs fine on the generator. Cord looks good. Kept running my tester around listening for 2 beeps. Kept only getting one beep at the same place. Cord looks perfect here. Cut it open anyway and find a factory splice from the cord manufacturer. Well I guess it worked for 20 years.

Nice find.

Electrical gremlins can be a real pain . I just finished helping my brother track down a problem he had with an old golf cart. He had replaced a couple of solenoids and a switch but couldn't get it to run. We checked every wire on it for continuity and finally started checking grounds and connections.
We finally tracked down the problem when we found a bare wire that was pinched under a clamp. After we spliced it together and taped it , it ran like new.

This makes me long for the old days when many connections were soldered, not crimped with cheap plastic connectors that get hot and melt.

Corroded/poor connections were my bread and butter back when I serviced electronics. On some units my first step was to cut out the main connectors and solder all the wires. Suddenly they worked and the intermittent gremlins went away. These connectors save a lot of assembly time but they are a time bomb to users years later.

Good luck with "magic electrons"