One fuse, maybe it just got tired, if more than one fuse has blown, you definitely have a problem. Time to get out the meter and do some trouble shooting. I don't have any specifics about your radar so can't help. If you don't have wiring diagrams, perhaps it is time to seek professional help. when I was having problems, it turned out to be a loose ground connection buried in an outsite cubby. Might want to check all your connections, especially if they are just crimped.
