Regarding the horn problem, I had the same thing on my 2002 wagon. There are two separate horns - a low tone horn and a high tone horn. Sounds like your low tone horn may have failed.
A replacement horn costs about $50 and is fairly easy to replace. They are located behind the passenger fog light assembly. It is relatively simple to remove the lower grill piece, the fog light assembly, and then the horn.
Of course check the fuse and relay first.