Electrical Issues

1995 Georgie Boy with a Kohler generator. Generator runs great, no issues whatsoever. Here is the problem. To start the generator, the ignition must be turn to the accessories position. Once started, you can remove the key from the ignition. Generator powers everything inside the motorhome when it is running. Once turned off, there is no 12v power inside: lights, etc. Recently had a new solenoid put in it and the tech said he "hard-wired" it. Not sure what that means. The cutoff switch for either using or storing the battery no longer works as well. Tailgate season starts soon...help!