I have a 1994 Nissan D21 which I have had problems with the horn blowing fuses before. I just recently replaced the horn and everything was working fine for a couple of weeks. A week ago, I was sitting my truck and noticed the Air Conditioning had stopped working, I tried turning the a/c off then on but it still did not work. I turned my truck off and then back on and it came back on. A few minutes later, I drove off and turned the radio up and it stopped playing music but still had power to the radio. The next day, I was backing up, blew my horn and the fuse had blown. When I pulled out on the highway, I realized my turn signals would not work. I tried my flashers and they are working. Any idea of where I need to start looking? I brought it to a mechanic and he sat on it for a week then went on vacation.
Looks like you may need to do some tracing in the wiring. Use the wiring diagram provided to assist in tracing the wiring harness.