keep blowing fuse for PCM???

[Mr.Duff99V8SHO]

the 15a (mini)fuse under the hood for the horn/PCM keeps blowing on me...the only way i knew it blew was cause its the same fuse for the horn, no check engin light or anything....anybody have any ideas what might be causing that??and could it possibly have something to do with a clogged cat??(im convinced i have a bad cat)

 

[mholhut]

I don't know if the 99's are different, but the 15A mini fuse for the horn is not related to the PCM on my car. If the PCM fuse blew, the car wouldn't run. The PCM fuse is labled "EEC PWR" and is a large 30A on the top row, furtherst to the left. On my car, they appear to be unrelated circuits and should not effect each other.

If the 15A mini fuse for your horn keeps blowing, then you probably: 1. have a short in one of the wires to the horn (seen this on my 94 SHO) or 2. have a blown horn relay. The horn relay is on the top row, second from the right... it's a grey box.

You sure this fuse is under the hood and not under the dash? Either way, it makes no sense.

 

[Mr.Duff99V8SHO]

its definetely under the hood...the owners manual says its the horn/pcm fuse...but the manual also list another fuse for the pcm so i dont know...?????the one that keeps blowing is #18 or 19 in the owners manual for the fuse box under the hood..