90 civic brake light & horn HELP

hey i have a 90 civic hb and my brake lights and my horn do not work. it is because the fuse is blown under the hood. if i replace it, the horn will work but as soon as i touch the brake pedal, the fuse blows. also, keeping the horn pressed and pressing the brake pedal u can hear the horn slowly die out and then the fuse goes. could it be the brake pedal switch?? any help please if anyone knows anything about this please help. thank you

Basically your wires have either melted together over the years and are touching in one spot, or they are cut and grounding out somewhere, causing a short. You need to trace the wires for your brake lights/ horn and check for any cuts/ grounding.