Well if you read the first part of my post #16 again, you had said that the dash battery lamp did not illuminate until about 1-2 minutes after the engine was started......which could have been the time when the interconnect relay closed to connect the coach and chassis batteries together for charging from the alternator. You had also said that you had purposely totally discharged the coach battery. So possibly the alternator was now trying to charge a totally discharged coach battery plus if the use/store switch (coach latching relay) was on, it would be feeding the coach DC fuse panel loads and also be connected to the output side of your failed converter. So “perhaps” the damaged output of the converter (you say shorted? Not sure about that though.) had “some additional impact” on the alternator output voltage.
__________________
|