QuestionI have a 2004 Hyundia Sonata GLS. The horn goes off without warning when parked and also when driving. It will stay on for about 30 seconds and then stop. This can happen three or four times in a matter of 20 minuets. I'm told I need to replace the fuse box, apperantly a fuse box runs about $1000.00 any other ideas?
AnswerI'm presuming that by "horn," you are referring to the horn activated by the steering wheel pad, not the alarm siren.
While it's possible that there could be an intermittent short in the underhood fuse box causing the horn to sound, this is a somewhat dubious diagnosis. More likely, there's unintentional contact in the steering wheel contacts or the wire between the horn relay and steering wheel contacts is rubbing and intermittently touching a metal component.
To diagnose, the first thing I'd suggest is removing the air bag and checking the steering wheel contacts. ****Make sure the battery is disconnected and has been disconnected for at least 20 minutes before attempting service on any air bag component.**** Make sure none of the insulators appear cracked or broken and make sure none of the wires at the steering wheel have cut insulation. If you find no issue, you can remove and tape the horn contact connector and see if the problem continues. If it doesn't, you'll know the problem was with the contacts.
Of course, if you're simply looking to make the problem go away and don't care if your horn operates, you can simply remove the horn relay from the underhood relay box.
