05 pacifica no horn
 

I thought it would be the clockspring, but everything else on steering wheel works. Only non function is the horn, any ideas

At least you were thinking...But what have you checked/tested? How long has the horn not worked? Fuse, relay horns themselves??????

This has been an issue for awhile (6+ months). I have not checked fuses or relays yet. Can't find fuse box or diagram of fuses to know which one.

so I've checked fuse and relays and those are good. How to check horn itself or even clockspring, if everything else on steering wheel is working?

Testing the horn is easy.
1st: locate the horn.
2nd: disconnect wire/s from horn.
3rd: connect the horn directly to 12 volt source.
4th: if the horn scares the crap out of you when it makes noise, change pants.
5th: Connect volt meter to wire/s that were connected to the horn, and have someone try to sound the horn, look for signs of voltage reaching the horn.

I had an issue similar to this. Bad ground is what it turned out to be, search google for South Main Auto Pacifica and you'll see an issue Eric O tracked down to a bad ground under the battery.

Another electrical gremlin I had I traced back to a PAC Steering Wheel Control Interface for my Pioneer. Caused all sorts of grief.