horns not working

i have a 2000 gmc sierra 1500 z71 stepside, the horns don't work, the fuse is blown, i can put in a new fuse in and the horns work a couple times, then quit, then i push the horns a couple more times and i can hear the relay working, then that quits, and the fuse is blown again. where should i be looking for this short?? any ideas??

I want to bump this up, becasue I'm having the same problem!!!

Thanks in advance!!

I have had to replace my relays several times on this vehicle. Not sure why but the relays seem to be weak. they last for about 1 yr then need replacing. The other option is to check to connections at the horn. I cleaned mine and the relays seem to last a little longer. Good news is the air conditioner relay is the same. There are 3 that are identical in the electrical box under the hood. Usually OEM they are grey in color.