Help with Blown Fuses

[Miniton]

When I turn on wether the nav/anc lights or the blower the fuse immediately blows. All other items such as radio, bilge etc.. All work fine. I did replace the radio and fish finder but literally swapped wires as I replaced each one. I tried disconnecting fish finder and tried nav lights but same issue, immediately blown. They were workin fine last week. Any ideas or suggestions are appreciated.

 

[glenn property of pam]

a blown fuse is normally a dead short. A wire might have been knocked off / nipped while you was working on the radio or if it was a tight squeeze the radio metal casing makes a great ground point when jammed against a live terminal. Do a web search on how to find a wire short 12v theres lots of different ways and people have made videos that are easier to understand than my writing skills.