Bought a 2010 Civic LX and the first day the security system went off with lights flashing and horn honking until I got to a mechanic who showed me the disable procedure (lock-unlock the door) which stopped the alarm, but now the horn doesn't work, which won't be good when I go for inspection. The fuse under the hood checks out, and other than trying to reboot the electronics by disconnecting the battery, I don't have a clue. Any other ideas much appreciated.

 

welcome to the forum. if you can find out the the maker of the alarm sys, you might call them and see if you can get a wire diagram to put the horn back to original if you are not using the alarm. sometimes there is an inline fuse near the battery.

 

Checked the fuse, hear a clicking from the relay switch in the fuse box when I press the horn, so I know both those work, removed the horn and wire it to the battery and it blows! So while I contemplated jerry-rigging a separate circuit with a switch on the dash for the horn, I figured I should give my stupid reboot idea a whirl, so I disconnected the negative terminal of my battery, reconnected it, and voila! My stupid idea worked, horn works fine.

Dear Honda engineers, please keep the horn on a separate circuit! I need a horn, not your silly theft protection idea.

Sincerely,
New Honda Owner

 

Thanks for the feed back and fix, and yes all car horns should have a separate circuit from the alarm or override.