Help needed Sdl after major!

google is your friend:
https://www.google.com/search?q=motronic+5.2+pinout&newwindow=1&tbm=isch&tbo=u&source=univ&sa=X&ei=NVi6VLu6KMSeyAT6iYD4Dw&ved=0CB8QsAQ&biw=1366&bih=673

What's a "footy oval?"

 

Steve

An open circuit in this application means a broken wire or a bad connector. Do a search on posts started by me, with 355 wiring ECU in the search terms and you will find all ECU pins and their functions.

This is not a hard problem to troubleshoot. Good luck.

 

http://www.ferrarichat.com/forum/348-355-sponsored-bradan/444614-f355-ecu-pin-out-wiring-colors.html

Mitchells pin out post. If you have a 5.2 355, there are three cat ecu outputs. I can only identify the cat TC on that list. I don't see where the center TC is.

In my opinion the best way to troubleshoot this problem is to tap the output wires from the cat ecus and monitor what they are sending the main ecu real time.

I extensively tested this issue and found that for whatever reason, bench testing the components does not necessarily prove it insitu.

I currently still have the tapped leads in my car as I am working on an alternative to the OEM cat ecus, but if you want to clearly and quickly get a grip on what is going on tapping and monitoring the ecu outputs realtime will tell you all you need to know.

 

given this issue, happened just after a major.. more then likely the wiring when pulled through the firewall, to drop the engine, got sliced.. causing a bad ground/open circuit..

I have a Euro spec 355, which i assume would be the same for UK car.. there are only 2 cat ECUs and 2 Thermo couplers. one for each cat.. there is no Bypass ECU/tc..

I had the same issue when I bought my car.. first the sdl bulb was removed from dash at some point in the past. once replaced it flashed no matter what..
tested, tc they were good..
test Cat ecu's.. both were dead..
replaced both Cat ecus with the new green ones.. still same problem.. SDL flashed no matter what.. even bone cold start.

my mechanic went nuts.. troubleshooting every angle.. thought maybe it was a bad engine ECU..

after more investigation.. went through all the wiring.. and voila.. there was a open wire..

fixed the wiring..problem solved..!

 

I will check with my Mechanic on Monday to see which pin on the ecu it is..
myself unfortunately I dont know.. so i'll see if he remembers..

 

If you look at the link I posted it is 14 and 15. As there is no bypass Tc on that list I would think that is a euro spec pin out.

I'm going to put a tone generator on my bypass signal wire and see which pin it is. I'll verify the r and l cat ones as well

 

I ohm'd out the TC outputs on my 5.2 car. There are three. Right and left cats and bypass.

As per the pinouts in Mitch's post above:

Right cat is 14
Left cat is 15

in addition I determined that the bypass TC is 74.

These are the pin locations for the signal wire off of the exhaust ECU.

In addition, I noted that when the ECU signal connector is connected to the ECU, there is an additional pin being used and that is 26. This is a common pin for all three ECUs. Mind you I used the taps I have on the signal wires so I was able to do this with the plug connected to the ECUs. If you unplug the connector to get at the signal wire as opposed to tapping it you will not have a reading on 26.

I just did a continuity test on the leads so I do not have a resistance value for them.


Here are some pictures of the main ECU plug and the female locations for 14/15 and 74.

I would suggest you unplug the connector from the exhaust ecu and see if you can confirm continuity as per above.

The first pic below is a schematic of the connector side of the plug, not the ECU side. Note the housing shapes in the image. The right side of the image (pin1) is the clamp side or harness side of the connector. The left side of the image is the fulcrum side of the connector, away from the harness.
Image Unavailable, Please Login
Image Unavailable, Please Login
Image Unavailable, Please Login
Image Unavailable, Please Login

 

I decided that pin 42 previously "function unknown" is the bypass valve TCU analog output.

 

Mitchell. Did you just see my post? I just did that.

 

Also to note the cat ecu's may have been disconnected during the engine out. It is possible the disturbance of that may now play a part in the light being on or flashing. Good point on the harness going through the body as its a tight fit and may have rubbed through.. Agree on the bench testing Vs real life use taking into account the heat in the engine bay..