You don't have to pull the converter to check it out. Just take the whole front cover off. (it has funny screws )
If there is a danger of water being there, don't plug the shore power cable in!!
The 7300 trouble shooting guide is simple to follow. it is on line. You can't get 46VAC "out". You get DC out with 120v "in" That 120 is "hardwired" with a black wire to a breaker and a white wire to a neutral buss. ( No ground wire)
You need 120v at the breaker panel to start with, then see what DC out is where the converter output (blue for pos, white for neg) goes to the lugs on the DC fuse panel. Measure DC at the lugs. Should be 13.8ish. If it is only 12.x, then that is from your battery, which goes to the same lugs.