My PT Cruiser's horn was fine until yesterday. Now it sounds like a sick moose. What could be the problem? Everything else is ok.

try this site to see if it helps you out. http://www.ptcruiserlinks.com/forum/sound-security-forum/29865-horn-not-working-fuses-not-blown-2008-pt-cruiser-lx.html

this link is the wiring diagram check it out as well.

https://images.search.yahoo.com/search/images?p=2008+PT+Cruiser+horn+circuit+diagram&fr=yset_widemail_chr_win&imgurl=http%3A%2F%2Fimg.photobucket.com%2Falbums%2Fv70%2FCREWZIN%2FHelpful%2520Photos%2FSteeringwheel.jpg#id=6&iurl=https%3A%2F%2Fi2.wp.com%2Finterkulinterpretor.com%2Fwp-content%2Fuploads%2F2006-pt-cruiser-cooling-fan-wiring-diagram-2007-chrysler-300-schematics-for-2005-hbphelp-or.jpg&action=click

http://www.bbbind.com/free_tsb.html Ok here is a wiring diagram for the horn circuit on your 06 PT Cruiser . Enter your vehicle info year , make , model and engine size . Under system click on interior & driver Amenity . Under subsystem click horn . You will see

1 diagrams found. with a search button under it , click search . Click on the blue link and then your horn diagram will pop up . It's probably nothing your going to understand . Do you have a air bag light lit on the instrument cluster ? Do you know anything about computer controlled systems on automobiles ? C.A.N - controller area network ? You should read this before you mess with any wiring How to Diagnose Controller Area Network CAN Also google chrysler TIPM - totally intergated power modul problems .

First figure out if it's the horn or the switch. Go out and hit the panic button on your fob. Does the horn go off?OK, it's not the horn. Your problem is in the switch in the steering column. possibly the clock spring.

Sounds like your alternator bearing are worn and will need to be replaced soon. Keep an eye on your alternator charging system, it may still be working fine (13.5-14.5 volts) but the bearing is warn and the alternator will fail when it does fail 100%.
Have your alternator inspected and replace it before winter comes.
Thank you for using fixya and be safe.

The horn needs to be replaced if it is a weak sounding unit now

replace the horn

The internals of the horn failed or one of the two pitches went out, replacement is quite easy. You can either buy a direct fit horn from Chrysler or go to an auto parts store and buy a generic horn. The generic horn will require you to cut the wires, but it is quite easy and directions are usually provided

Where is the fuse for the horn on a PT Cruiser

bad battery connection

The horn is located in the front fenderwell on the passenger side behind the inner fender. You can't see it until the inner fender is taken out of the way.