Audio Systems: Electrical short, infinity sound, 2001 chrysler 300m

Question
About a month ago my husband had speakers installed in the font of his car. It is a 2001 Chrysler 300M and they replaced only the 2 front, midlines, and the tweeters. About 2 weeks ago he used the keyless remote to lock the doors and the horn made a funny sound as it locked and the fuse blew. When he tried to turn on the radio there was no sound and the fuse for the horn blows before you can even put it in all the way. So I think it may be the amplifier which happens to be connected to the horn. I'm looking for a simple test before I have to spend an arm and a leg to either replace it or find the short. I know very little about the stereo system I can do basic electrical but the amp eludes me. Any help would be much appreciated. Oh and the fuse directly on the amp, which is stock infinity, is fine much of the reason I didn't suspect it at first. Thanks,
Beth

Answer
some chrysler infinity sound system comes with 3 amplifiers  it is posible that there is two more amplifiers 1 on each door

replacing the speakers in that car was a very bad idea  you can only replace the door speakers with the same infinity original sound system  because they are 1.5 ohms NOT 4  
the best thing to do now is to open the doors and check the cables if everything ok umplug the plugs behind the speakers/amplifier  and try the fuse again
good luck