Kia honks by itself - Kia Cars & Trucks

The horn works off "Ground". Your horn wire is grounding out somewhere.

Either the horn itself is grounding on something or the hornpad on the steering wheel is making contact when it shouldn't be. Or maybe an aftermarket alarm is causing the problem.

I pulled the center out of the steering wheel and grounded the horn contact. The horn honked like it should. This is on our 2006 KIA Sedona. The horn used to work once in awhile, but not at all now. This leads me to believe that the clockspring in the steering column is defective. I will call the dealer on Monday to see if there is a warranty fix, but I doubt that there is.

One honk means all doors are closed. Door ajar you have 2 honks telling you a door is open. My 03 Explorer has had the door ajar light on for awhile

If blowing fuse when honking horn you have a bad ground to the horn or the horn itself has a internail switch. Try using a higher amp fuse, good luck

there is an alarm somewhere on the system try disconnect it

The fob is infamous for its battery life. It gets drained so quickly that there happens to be a little later when the fob is very close to the door lock, ignition & unnecessary triggers the alarm due to low reception as the battery of the fobs discharges very fast, depending on the model, which has a certain virtual sheild(STARTRECK type) which is triggered by the fobs strength of the signal(radi waves).

Why not try a new set of batteries for your fob?? .................................sodeep

You can remove the horn relay and use a Ohm meter and check the resistance between the horn relay connector terminal No. 86 (Black Wire) and ground. If the ohms are less then 5 ohms replace the horn relay. There are a lot more tests but as Polarcycle states you can do what he suggested other then I believe you have two horns in this vehicle.

Check the horn actuating contact at the centre of the steering wheel. It may be damaged or mis-aligned.
Also check the carbon contact that runs on the slip ring under the steering wheel (associated with steering wheel horn actuate switch) It may be damaged or mis-aligned.

If none of the above are faulty, you should look for a possible intermittent short to ground on the horn actuation control wiring.

It sound like the horn is the problem. You may need to purchase a new horn located in the front grill somewhere. I hope this helps.