check the model number then go to You are today’s WINNER!
and go under manual for your convertor model and look up testing .
when my wfco convertor went bad i replace just the convertor portion and reused the wfco frame and circuits . I bought a 75 amp convertor from intelli power and installed it in the wfco frame.
I did have to do some mods to get it to fit but was very minor.
I also got the charger wizard for it .