Hey guys over the weekend I removed my stock horn and installed a used air horn from my brother inlaw. It plugged right up to the stock wiring without any modifications. It worked for a few seconds then I blew the fuse. I replaced the 10 amp fuse with a 30 amp fuse and now it works fine. However when I blow the horn my headlights and fog lights flicker ever so slightly,Is there something else I should do or is there something wrong? By the way I have a 2011 rubi unlimited.

 

The first thing you did wrong is replace a 10 amp fuse with a 30 amp fuse. That's asking for trouble.
Not only is the wiring inadequate for 30 amps, I'll bet the relay is marginally capably of carrying 30 amps.

 

Take that thirty amp fuse out. You ARE over drawing the horn circuit. You WILL have problems. Research aftermarket horn kits for options.

 

Thanks guys didn't realize that.

 

Run a #10 wire from the battery to a relay, and from the relay to the new horn. Use the stock horn wire to trigger the relay. Put a 30 amp fuse or circuit breaker in the #10 wire as close to the battery as possible. If you arn't familiar with how to wire a relay, there should be tons of how-to write-ups on this site or elsewhere.