348 - phantom blower

Sounds like it, unless you want to take one out of a car I've got in stock and try that

 

Mine does that. It will do it several times on one drive, or not do it at all for several months. Something to fix someday.

 

Its your HVAC ECU malfuctioning, mine did that too. When I replaced mine for another reason the problem never came back. Regards, Vern

 

Start here: http://webpages.charter.net/aircover/348/1994Ferrari348Spider.html#AirConditioning

Our 348's all have a self-diagnositc mode. Put your HVAC into that diagnostic mode to see if the problem is a motor/actuator/sensor/electrical fault. Fchatters have reported time and again (e.g. E5 error code) that the diagnostic mode nails problems.

In the U.S. 348's, there are some common ground crimp pins behind the left side AC vent. These same ground crimp pins might be reversed on UK models (I'm just not sure).

But I solved at least one of my HVAC problems by coating each pin and crimp connector (bottom right in grey in the picture) on those common ground points with Stabliant 22a.
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IIRC the HVAC ECU will flash a default code if there is a problem that does not meet its programed guide lines. My intermittent fan problem did not flash a code or store in its memory anything related to it. ie the computer would have flashed a default code if it knew what the fan problem was. You wouldn't have to read the stored memory because there was no flashing code in the first place. My problem didn't relate to the ground problem either because I check that also, That doesn't mean it couldn't be that, given the stupid concept used for the ground on the 348s. They changed that on 355s and later cars, I am sure because of corrosion problems. After I finally changed my ECU my fan problem went away. Regards, Vern

FYI those computers are 1200.00 if you can find one. It took several calls to dealers around the country a few years ago to locate one. I was told at that time that Ferrari wasn't making them anymore, I don't know if that still true or not.

 

The system doesn't always see some behavior as an error. For instance, if a temp sensor is reporting very cold, then your heater is going to come on to bring up the cockpit temperature.

The HVAC diagnostic "mode 3" lets you see the values that all of the sensors are reporting.

In "mode 4" you can force each of the actuators open/closed (or in between) while running the blower.

So between mode 3, mode 4, and the E1 through E9 error codes you can do a fair amount of do-it-yourself debugging.

After that, Stabliant 22a on the ground pins *has* fixed some HVAC issues. It fixed my blower motor from cutting out at random times, for instance.

If none of that works, then I'd take apart the HVAC ecu (in fact, I did this to my car) and apply Stabilant 22a on each solder connection and on each pin of the circuit boards inside that black box. Doing that fixed my clock display.

Other things to fix before replacing the HVAC ecu would be to get a new car battery and ground strap. If the HVAC problem persists then I'd suggest testing/replacing the alternator/ground strap.

Failing all of the above it would be time to replace the HVAC ecu itself ($$$$.$$).

 

Wink wink... I have two of those computers, brand new in the box. They ain't cheap. I paid way more than $1200 each for them.

http://ricambiamerica.com/product_info.php?products_id=201897

 

I think I am fairly competent in the how the ECU works on a 348 and how the diagnostic program and its function work also. My point was that in most of the cases I've seen (4) that there wasn't anything that could be done for the exiting ECU short of spending hours(and$) running down which electrical component was not doin' its job. So its a trade off spend the dollars running down the problem or spendng those $s on the new piece. My end result was what's quoted at the top.

 

Hi Daniel, You have two of those huh? They must be making them again. Yea, that 1200.00 was a quote about 5 years ago. I still have one that is malfuctioning, one of these days I'll have to get it out and chase down it's problem. Regards, Vern

 

Nope, these have build dates from 1993. Brand "new".

 

It's one thing to spend $1200++ on a new climate control ECU and have it fix the problem (permanently?).

It's another thing to spend $1200++ on a new climate control ECU and still have the same problem, if it turns out that something else is wrong.

It's a VERY complicated system. I had my brother (who ain't scared of electronicx like I am) look over my ECU, and he couldn't see anything wrong with it, but how would you know where to look?

For now, I'll live with the "phantom blower". But I'll be interested to hear if anyone has other suggestions on how to diagnose and repair it.

 

I agree completely it is complicated. I had the same problem with the fan that you have and lived with it too. I didn't change mine for that reason my ECU just up and quit one day. After spending countless hours cleaning ground points, trying to read fault codes which, by the way there weren't any, turning the stupid thing inside out I bought a new one. The secondary plus for me was that fan problem went away. Trouble with electronic stuff is is that what causes your fan to act up and what caused mine to act up are probably 2 different things. Intermittent problems like this are impossible to track down, they have to happening at the same you are looking for them. Regards, Vern

 

Really!? so when the're gone the're gone, huh

 

Hey guys!

Can anyone tell me where exactly the HVAC control unit is?

Thanks

 

In your center console below the radio with all the buttons and the clock.

 

The whole unit, I see. Love these simple older cars.

Thanks again!