My owners manual (page C12) says the following: "By using the special push button situated near the central unit, after connecting it with the diagnosis socket, more details on the kind of trouble are supplied." Then shows a diagram with the push button located next to the main ECUs (central units) behind the seats. I found the diagnosis socket they speak of next to both ECUs, but can't locate the "push button" they speak of that plugs into it. Is this push button something that I should have, or is it something I need to purchase? What exactly will it tell me and how? If I do have to purchase it, how much? Thanks, Chris
Don't just push the button. If I remeber correctly it resets the ECU. If you do happen to push it you must let the car idle without touching the accelerator for at least 15 minutes. Anyway the button is located right next to the ECU, not on it, on either the upper right or left corner of where the ECU is located.
Is it possible that your car has the Motronic 2.5 ECU's without the self-diagnosis function? If you have the 2.7 system, the push buttons should be right where they appear on figure 4, page C12, item #3, attached to the end of the cable for the diagnosis socket. Do you know the procedure for downloading stored codes and interpreting them, and clearing the ECU memory? It is described in detail in the Workshop Manual.
It is the 2.7, so I guess I should have the button, however it is definately not there. It must have dissapeared with the prior owner. Do you happen to know where in the workshop manual the information on downloading is? Thanks for all the help so far.
92-348ts (Chris): Sorry for no reply, I haven't been home. The Workshop Manual describes the "Self Diagnosis" procedure on pages C78-C81. It's easy. Your Motronic ECU should look like the one I will picture here. This is the passenger side unit. The button is in the lower left corner. The pigtails for the diagnostic connector can be seen. They are normally left unplugged, and only plugged together when doing the self diagnosis. If your buttons are missing, are the holes there that the buttons should fit into? Seems very strange that they wouldn't be there... Keep us posted. Jeff B.
Jeff- Have you ever had one of those days... Here is a picture of my passenger side ECU. I have the mounts for the button like yours, however no buttons for either ECU. I called the dealership I purchased the car from and they have no idea why they are missing. Still waiting to hear back from them on replacement cost. Also, I looked through my workshop manual and it turns out the book I have is for the earlier Motronic 2.5, not the 2.7. If interested, I would be more than happy to cover the cost of printing/postage if you wouldn't mind burning me a copy of those four pages you spoke of, or even just simply faxing me a copy.
Hi, Chris: Very strange, indeed. There is no reason on earth why your car should be missing the buttons, but... My parts book says the button is #145810 and the short cable for the button is #146196. If they are outrageously spendy, I suppose you could buy one of each and switch them from side to side, since you can only test one ECU at a time. Someone might have used ones (maybe from YOUR car - ha!) I don't have access to a FAX. I can photocopy and mail the diagnosis pages, or email them to you, might take a while to load/download, but I don't care. Your call. Happy to do it if it will help. Hope nothing else is missing. Jeff B.
The self-test buttons are normally connected, that's the way the cars were delivered when new. My guess is this is what happens as these cars age, someone has a reason to disconnect and not reconnect (SD1 testing) and someone else decides to pull the buttons out entirely, who knows? You can test both ECUs simultaneously, I've done it hundreds of times. Best regards, Rob Schermerhorn
Rexrcr has far greater experience than I and knows of what he speaks. However, the handbook tells you to use the push button after connecting it with the diagnosis socket, so there is apparently no reason why it should left plugged in. Doesn't matter. You only need one button and one pigtail, and it does not need to be attached to the hole in the car. Keep it in your toolbox if you want. Rexrcr may be able to keep track of the flashes while doing both ECU's simultaneously, I wouldn't even try it.
Jeff- I sent you a private message with all my information. If it didn't work, let me know and I will repost the info on this thread. Thanks again. Rob- I just got the price back on the buttons ($60 a side). Is the information these buttons supply going to be enough to justify the $120, or do you think it would just be a waist of money?
Actually, the buttons only close two terminals which puts it into self-diagnostic mode, so I guess you really only need a piece of wire I don't know which two leads though, never had this problem. If authenticity matters... Functionally, just jump the terminals (but read the WSM first).
Chris: I did not receive an email from you. Try me at <[email protected]> I did some looking at the car and at the shop manual. They are contradicting, and I don't know why. The manual shows that pushing the button connects terminal "A" (grey/red wire) with terminal "C" (grey/brown wire). In fact, terminal "C" is blank on the pigtail (and they are NOT internally connected), and pushing the button connects terminal "A" with terminal "B" (black wire). I checked both sides, they are the same (at least on my 1990 348ts with Motronic 2.7 system). The manual appears to be wrong, but I have no way of verifying it one way or the other. All I can say is that on my car the self diagnosis works fine, and pushing the button connects the grey/red wire with the black wire. You could probably make one of these test button/pigtails with about $2.00 worth of bits from Radio Shack, or just jump the terminals with a test wire. But at this point, I would want to be very, very sure that your car is the same as mine before proceeding. Perhaps your local dealer could verify the color codes????
Can anyone confirm one way or another if this is correct for ANY year 348? Rexrcr? It is NOT correct for my 1990 348 with Motronic 2.7. 216a is the pushbutton, 215a is the "diagnostic socket" (pigtail connector). HR = Grey/Red HM = Grey/Brown N = Black
I'd go with the wiring you're holding in your hand, not the schematic. I bet black is a ground to the ECU. This should be for all Motronic 2.7, including F355, 512, 456. A dealer will only have the same schematic. Strong work. Rob
Hi All Note that European 348s didn't get delivered with the disagnostics cable. In Europe you need to go to your Ferrari dealer to get the codes read out. However, I asked whether it is worth ordering (or building) the button and adding the blink code lights (these are also missing in European models) and was told that it wasn't really worth it because only a few simple error codes are given using this method. Only the test equipments can pull "all" of the error codes. Is this true?? Regards Mark
First of all, WOW you dug up an OLD thread. As for what you were told = not true. You can pull a LOT of codes from the OBD I Motronic ecu's with the button. It is totally worth making/buying the button, and will end up saving you a lot of money by allowing you to pull the error codes yourself.
Hahahaaa, that is a good laugh reading that oldass post of mine. Just pushing the button will NOT erase the codes, and you ONLY have to let the car relearn the warm up parameters if power is cut from the Motronic ecu's, as it erases the learned info from the memory. Boy oh boy did I learn a lot since then, and I still don't know jack. LOL!
I believe they were lost during the great Fchat server crash (note the post dates from 2003). I've also heard recently that the button and connector cable is NLA, so if they are missing on a US model (they did not come on Euro models) they will either have to be bought used or fabricated.
If you want, check out the site my348 dot com. It's a wealth of info frequently referencing threads back here. I believe there's a link on how to make your own buttons or to even use wire to retrieve the codes.
