How embarrassing....348 horn has mind of its own

From my experience Pete, its just sticking relays.

But see how you go after you fit the new ones.

 

If the problem continues you may be in for a new horn pad switch. On some vehicles this comes with the airbag.

I'll see what I can find for info.

 

Nice one T-MAN. But dont stress mate, the 348 never came with an airbag.

If anything, the horn button may be on its way out. But I doubt it.

Also, the relay's are much cheaper than the horn button so I would replace both relay's first and go from there.

 

It seems my service info doesn't cater to Ferrari. Looking at a few examples yours seems to be a simple switch and slider ring in the hub or column.

I located a button and hub on ebay.

http://cgi.ebay.com/ebaymotors/FERRARI-348-STEERING-WHEEL-HUB-AND-HORN-BUTTON_W0QQitemZ180469898059QQcmdZViewItemQQimsxZ20100217?IMSfp=TL100217192011r11384#ht_624wt_723

 

I concur.

Most times I'll swap them with another component say, the fog lights or defroster as a test.

 

Why fix the wimpy Italia-tooter?

I've got a Motorola HD Emergency Vehicle Siren module for sale. And how often do you use "Hi-Lo, Whelp, and Wail in normal conversation.

What does one do after pulling over a cop with a Ferrari? Probably best to cover plates before pressing 'ON'.

 

I concur.

Most times I'll swap them with another component say, the fog lights or defroster as a test.

 

sounds about right
or thats wat happens when ferrari's reach pubity
they do have a mind of their own sometimes

 

I apologize for the double post. Posting from a smart phone isn't without it's perils.

 

I could see the horn going off & sticking if you had pressed the horn. But what would cause the relay to stick in the on position in first place?

I'd think it's a short. Probably in the column.

 

Peter;

Are you aware that the 348 steering wheel has horn contacts in the spokes, as well as on the center button? I had my 348 for five years before I discovered that! Duh.

I wouldn't be surprised if your problem is that the contacts in the spokes are pushed together and completing the circuit to activate the horn, even if the center button isn't being pushed.

I did an extensive thread a couple of years ago about diagnosing an issue with the horn on another members 348. I'm sure it's in the archives. I'll look. Edit: Here it is.

http://www.ferrarichat.com/forum/showthread.php?t=56370&highlight=horn+brent

 

The horn presents a considerable inductive load. As such a great amount of sparking at the contacts which commonly causes them to weld together. The other failure mode is pitting causing no contact.

You have witnessed the effect on distributor points, which require a condenser (capacitor) to nullify the coil's inductive load. Only brute force of the rotor keeps them from welding shut.

You will often find relays with supression circuitry on the coils to prevent contact pitting or welding on an expensive switch which energizes them as coils themselves are an inductive load. Reducing inductive sparking from motor loads such as the horn compressor is generally ignored as the cost isn't worth the price of an inexpensive relay.