The 40A fuses in the converter were probably blown because the battery cables were installed backwards. Their function is to protect the converter. Check to see what color battery wire goes to chassis ground and install that on the battery negative post. The other one is positive. Your converter, if not already damaged, should then charge your battery when the trailer is connected to 120V AC shore power.
2012 Forest River V-Cross Vibe 826VFK
pulled by 2009 Ram 1500 Quad Cab Hemi