There is a very good chance that the generator merely needs to be flashed.
To do so,
1. Remove the spark plug wire.
2. Obtain an old extension cord that you can cut one end off, or an old power cord from an appliance (you will need the male end).
3. Note how on the receptacle, one slot is longer than the other. This longer slot is the negative slot. It is critical that you get it hooked up correctly.
4. Determine which wire of the cord will go to the negative slot.
5. Connect the negative wire to the negative terminal of a 12V battery.
6. Connect the positive wire to the positive terminal of the battery.
7. Plug the cord into the receptacle and pull the starter cord 6-8 times.
8. Immediately unplug the cord. DO NOT LEAVE THE CORD PLUGGED IN FOR MORE THAN 6 OR 8 SECONDS.
9. Disconnect the wires from the battery.
10. Reconnect the spark plug wire and see if the set is now producing electricity.
If this does not work, let me know - and we will dig deeper.