I couldn't find a wiring diagram for the 89'* but this one for the 90 LE & SE should work.
I didn't understand why you couldn't locate the horn relay. You posted a picture of a diagram that shows the location.

Levi, from the pics it looks like your relays are missing?? Did you or someone pull them out? I had an 89 but it was several years ago and I can't remember much about the fuses / relays. They are in a diff location on the one I own now I belive. Hmmm You say you DID unplug the cig lighter right? I had a penny stuck in a car I bought a long time ago and it was doing the same thing. Would randomly blow fuses when you hit a bump.
Man that could be hard to track down.
Rob

Technical Ted -

Thank you, the next time my friend comes by I will ask him to look at it. I found the horn relay, but there was not a fuse in it. So I was confused as to what I was supposed to do.

fritcr -

I have taken out any fuses from the relay board before, and to my knowledge no one else has either. Are they supposed to be empty? Unless the fuses for the relay recently fell out, they have been empty for awhile and the horn, radio, and the other things have been working. I did unplug the cigarette lighter but the problem persists.

Thank you both.

Levi

You're not looking for a fuse, pull the relay out, replace fuse #11 & see if it blows. If it doesn't blow then replace the relay. If it does blow then there must be a short to ground in the orange wire.