New to motorhome problems

Thanks for all your suggestions. I checked the voltage at the battery and they were 13.2V. I checked the voltage at the converter and that was 13.2V. The green light is lit up on the converter. After I checked everthing. Including circuit breakers and small fuses, put it all back together, it is still discharging. The manual that came with my motorhome says "the green LED signifies that 120V power is present and that the input fuse is intact. The converter should be operating normal." Could not find the input fuse. Not sure what accsys meant by " If it is, you have a bad connection between it and the battery. If it isn't, you need to make sure it is getting 120V AC. If not research why - it could be a circuit breaker or bad". Does that mean since I have 13.2V at the converter that its a bad connection? Shouldn't that mean a good connection. My neighbor, who is an electrician, helped me and he did all the testing. I guess I'll just have to buy a new converter. It's a 45 amp converter, but I dont know the model number. Once I get this problem straight, I want to sell it and, eventually purchase a larger unit still sticking with the class c.