Anyone have a similar issue on their 348? Just happened...
According to the book, the horn fuse is a big 25-amp one, so it takes a considerable draw to blow the fuse. If the compressor motor gets frozen, it's possible to bring it back to life by adding a few drops of lightweight oil to the air intake - I used Snap-On Air Tool Oil in mine. If it's totally burned out, you can replace it with a generic compressor at a fraction of the cost of a Ferrari compressor. You're sure you have the correct fuse in there, not a little 10-amp or something?
I have the right fuse in there 25 amp, tried a 30 just to see too but as soon as I put in a new fuse it blows it. So where is it this elusive compressor motor so that I may see if it is indeed frozen and see if I can drop in some lightweight oil to the air intake? And any thoughts on where one could fine (in Los Angeles) a generic Compressor if need be?
Sorry, been out walking the dog in the rain.... The compressor is under the same cover as the windshield washer tank, in the front trunk. I'm afraid I can't remember if the 348 compressor has a little flip-up lid for adding oil, you may have to just pull off the hose and put some in with an eyedropper, or something like that. You probably have to remove the trunk lining to get access to the bolt that holds the compressor into its bracket. For experimentation, you might want to just unplug the power wire from the compressor and hit the horn button, while there is a good fuse in the slot. If it still blows the fuse when the compressor is unplugged, then there is a short in the wiring. If the fuse does NOT blow, then there is an excessive load in the compressor, which theoretically should be fixed if you can get a little oil into it to free up the vanes. A generic air horn should be available through AutoZone/Pep Boys. Wouldn't require any new wiring, just plug in the power wire and the air hose to the trumpets, and you should be "good to go". It should sound exactly the same as the old one, if you keep the original trumpets.
Good info, I will let you know how it goes tomorrow when I undertake the project. Walking the dog in the rain? Ouch! I was walking our dogs earlier today too, but its 73 Degrees here in Los Angeles
Mine has been doing the same thing for about a year, I assumed it was the compressor, and I assume it probably seized up from lack of use... Thus, I haven't addressed it yet because I really haven't missed it!
Usually the contact on the compressor are held in place by hot glue. Yes, hot glue. The ones women use to mount colored stones to their dresses and shoes. When the hot glue gives up, sometimes the contact gets pushed inwards towards the inside of the compressor motor. When that happens, you are almost guaranteed to blow a fuse. Need to remove the compressor and make sure the prongs coming out of the compressor are tight.
Yup thats how I feel, went and picked up a after market compressor today and got in there and removed the old one. Plugged in the new one. Placed a new fuse in there and the fuse did not blow but the horn just kept on blowing. WTF? Ok, plugged in the old compressor just to check and see what happens and keeps blowing fuses? Again the new one does not blow fuses but the horn just blows (pardon me ladies). Any thoughts? And yes I had the positive connection and the negative one in the right place...
This sounds to me like more than one problem - I'm sure we can figure it out. Did you try the "experiment" I mentioned earlier? With the wires to the compressor unplugged, and a new fuse in place, what happens when you push the horn button? Does it still blow the fuse? Does it make any difference if you push the round center button or the buttons in the spokes? Are you sure that no one has swapped relays in the front circuit board? The horn relay is supposed to be a Bosch 0332014113, in position "D". Has the steering wheel been removed recently, or has anyone messed with the wiring under the pad in the steering wheel?
And did not blow any fuse. Nothing happens. No one has messed with anything, not the steering wheel or any where else.
OK - just to verify - when everything is attached, and a new fuse is plugged in, and you push the horn button, the fuse blows out - correct? And when you unplug the power wire from the compressor and push the horn button, the fuse does NOT blow out - correct? Do you have a 12V test light? Next step would be a couple of easy tests at the relay. Humor me - look at the horn relay, as indicated on the diagram on the lid - is it indeed a Bosch 0332014113?
No one has messed with anything, not the steering wheel or any where else. FYI when everything is connected and I plug in a fuse to the old compressor the fuse blows immediately. When I do it to the the new compressor as soon as I plug in the fuse the horn starts to blow and does not shut down until I pull the plug on it.
John, I sold my 348 a couple of months ago after owning it for 11 years. On Albert's horn problem, I'm still leaning towards there being TWO things wrong. #1: Either the old compressor is shorted out internally, or it's stuck. Given the description, that has to be the case. It obviously has power to the fuse, which means it has power to the relay. #2: Either the relay is stuck closed (it's normally open), or something is grounding the circuit that is normally not grounded until you press the horn button. There SHOULDN'T be power to the fuse (and hence to the compressor) until the horn button contacts are closed, to energize the coil in the relay, to close the relay contacts..... Make sense? Next step involves finding out why the relay is energized (closed) when it should be neutral (open). This is just my opinion, based on what I've been told so far.
Your relay is stuck open. Or, maybe the contact in the steering wheel are fused together. As mentioned above, you got to backtrack the lead wire and see where the culprit is.
Ok, Miltonian first of all thank you for all of your well informed input. It is truly appreciated but I am sorry to hear that you parted with your 348. Someone got a nice car. And thanks to all of the 348 brother that have piped in. So I did look at the relays with the 12V test light they are working correctly and the correct part is in there, actually old looking but working. But went and bought a new one today at Ferrari of BH. Same problem when I placed the new relay so yes I am going to need to backtrack the lead wire and why this is happening. Or most likely just take it to the shop since I cant seem to figure this one out. FYI, when the old compressor is in, even with the car off as soon as I place a new fuse it blows immediately. This is happening without touching the horn, just placing the new fuse in. And when I put it in the new compressor, and then the new fuse the compressor starts to blow like the horn is stuck on. Is it normal for the compressor to make a very winding noise when it is functioning? There you have it guys. If anyone has any other thoughts let me know.
Have you tried disconnecting the horn switch at the steering wheel. If you disconnect it and connect the new compressor and the compressor stays off, then you have a defective horn switch in addition to seized compressor, Should be easy to disconnect. Part is only $33 at Ricambi.
No I have not tried to disconnect the horn switch. But will do that tomorrow afternoon. In the morning am taking it out for a nice long drive! Is there anything I should or should not do in disconnecting the horn switch, do I pop it out from the front? or need to do something else?
I dont know exaclty on the 348 but from the ricambi site, parts diagram, it looks like it simply should pop out from the front.
12 v at the compressor leads means the relay is closed. But the relay could be closed from a bad horn switch or a stuck relay. I think he has already tried swapping relays. Diagnosis by internet, hardly an exact science.....
Ahh, I missed that in post #18 Jordan. You're right, he did swap out relays and the problem remained the same. Going to edit my earlier post right now. Sorry guys!!
