Horn Blows fuses and Backup lights don't work

the cig. light is a colpret its hooked to the same fuse or it is on my 93 stang i had a penny slip in there and it kept blowing and i'm like WTF so i went through the whole car and finally found it and now it doesn't blow anymore also the cig lighter will stick and blow the fuse so take the cig lighter out or just unhook the wire leading to the recepticle see if that works

I've also heard that if the horn itself is shorted out, it will just blow the fuses. Also, if this is on a 88, you might need to replace the foam in the horn button if it is honking by itself. The horn switch is two pieces of copper with foam in between. When you compress the foam, the horn honks. As the foam deteriorates, it will complete the circuit and honk by itself. I used some headliner foam about 1/8"-3/16" thick with holes cut out where the bumps are to replace my foam, others have found thin scotch brite pads or foam sponges that have worked. Just remove the horn pad and take it apart, it will be pretty obvious how to fix it. Just don't make it too thick or forget the cut outs, or it won't honk at all.

Good luck!

unplug the horn, plug in a test light and ground it, and then replace the fuse. If the light works when you press the horn button, and the fuse stays, the horn itself is the problem.

I had the same problem. Changed the horn and it went away. It went bad.