Fuse blowing

The rear window wiper quit working on my wife's 2007 Chrysler Town and Country. Now the fuse for the radio keeps blowing. I think the radio and rear wiper are the same fuse. My wife says the wiper quit about a week ago but the radio still worked. The odd thing is that I can replace the fuse and play the radio with the key in ACC without the engine running but as soon as I start the engine the fuse blows after about 5 sec. Does anyone have this problem? This has me stumped.