Does the fan not blow at all or does it work at full speed only ? In my experience if it works on full but not anything else then its definitely the sword, I also think that covers if it doesnt work at all, but Ive always at least at air on full.
With the sword out you can take it apart to see if you have cracks in the solder but they may all be too small to see. I havent bothered to fix mine in the past Ive just replaced it with a cheap spare and theyve always worked for me *touches wood*