that is internal to the vane is one thing and the wiring that connects it to your batteries
is a different thing. The first could be best troubleshot by someone knowlegable with that particular vane (best) or by another windvane
person. You might get good advice on that from someone who is familiar with alternators.
If the problem is with the wiring to the battery
system you only need someone who is qualified (often someone who has a boat
around you), or better by a general marine
electrician. You should check your fuse first, then all connections ( positive and negative). This is often the source of "wiring" problems. You need to be more specific though. Co you have a separate charge regulator
for the vane (like those for solar)? I would think so. It could also be the problem but it sounds like you need someone to do basic trouble shooting first which can be done by many cruisers who know how to do this with only a multimeter.