355 P1447 code

Hope this holiday season finds you all well.

Just got a 1998 Giallo cab F355 and have the check engine light on with a P1447code.
From this site I learned what the code means but not how to remedy - the "slow down" light does come on causing the "check engine" light to come on. The "slow down" light gets power, the bulb is good, but will not light up. (e.g. when i just turn the key before starting, not cranking- pic attached.) I guess that means ground??
Most everything I can find is about making the light go off or stop flickering, not to get it to work.

Also, after troubleshooting this, with the battery switched off and NOT disconnecting any cables to the cluster the airbag light is now on. Sigh.

I disconnected the batterry and le the car sit for 10 min then reconnected it but no help and the airbag light is still on.

The car runs great.

Thanks for your consideration and for any help.

Dave
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P1447 is either the right or left Cat thermocouple thus could be a bad thermocouple or a bad cat? Tons of threads on them.

https://www.ferrarichat.com/forum/threads/diagnostic-code.242188/
https://www.ferrarichat.com/forum/threads/f355-power-loss-and-bucking-losing-my-mind.369287/
https://www.ferrarichat.com/forum/threads/where-to-start-with-these-cel-codes.360348/

 

Im sure others can chine is as well. Good luck!

 

Check out Technistrada for solutions.

https://technistrada.com/

 

Yikes! I meant to post that the "slow down" light does NOT come on. (as shown in pic)
Can't figure out how to edit
Rookie mistake.
Thanks for your patience and advice.

 

The Motronics ECU provides the ground, so I guess it is not happy with the cat temperature system. I assume that P1447 is related to the cat temperature system, but this code is not included in my code list. I have P1446 and P1448, but not P1447.

Or it could be the SDL wiring (between the Motronics ECU and the binnacle)... or the binnacle wiring itself. If you run out of ideas, check the wiring between ECU pin 66 and the red/green wire on the right hand instrument binnacle plug.

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I'm not sure if the red/green wire is on pin 2 or 14 of the binnacle plug. Either way, it's the second pin from one of the ends of the plug and it should be next to the green/red power wire for the SDL.

Don't panic ... I guessed from the checks you were doing that the light was not coming on.

 

Regarding your Airbag light.... I'm not sure what's going on here, but anyway, you'll need to go to a Ferrari dealer to reset the light with an SD1 tool.

Is the right hand binnacle plug mating properly? Are the pins ok?

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I assume this is the message thread where you found the definition for code P1447.

https://www.ferrarichat.com/forum/threads/diagnostic-code.242188/#post-138627201

Nice to see someone using the FChat Search function

 

Yes, that was the thread as well as a couple of others on this board- very helpful.
I have had lots of Alfas (currently 5), but this is my first Fcar. Lots to learn...

Thank you so much.

 

@Qavion - YOU SO ROCK! It was the SDL wiring- The picture you posted was immensely helpful- made is easy to find the right pin, the fix really easy and saved hours of troubleshooting.
Worked like it should now and stayed that way after over 60 miles of driving. Should be able to pass inspection tomorrow.
Mille Grazie!!!!!
I'll start a new thread on the airbag light.

 

Excellent, but where, exactly, was the problem? In the binnacle, in the binnacle plug or between the binnacle plug and the engine ECU? I can’t say I’ve heard of this problem before.

I have 2 self-tapping screws holding in my binnacle. I have often wondered if they could pierce the wiring going to the binnacle.

Anyway, a great outcome. Finding problems just before inspection can be stressful. Thanks for the feedback.

By the way, how did you go with your airbag light?

 

Not just before inspection. I just bought the car. It is my first Fcar. I am familiar with and comfortable doing hack on my Alfas but i suspect that it is cheaper to keep everything properly maintained with this one. I want to keep everything right.

It was a flakey problem- disconnected the plug that goes to the ECU, tested for continuity to the binnacle, was fine, cleaned it up, plugged it back into the ECU and it worked. I'm used to Alfas so this did not seem odd. Knowing which pin it was made it quick. It should pass inspection now, the airbag light on isn't a reason to not pass in NY- I'll find out tomorrow.

WRT to the airbag light- the shop manual notes you can manually reset the light by grounding out pin 1 360, Reset manually airbag light. | FerrariChat (the thread was for a 360 but the procedure described was for a 355.) This seems too good to be true. In this thread you cast doubt on that 1997 355 Airbag diagnostic connector | FerrariChat any ideas? Could the reset trick work and the second thread have pertained to diagnostics only? The light stays on. that started when I took the binnacle off WITOUT disconnecting anything- I just removed the slow down light and verified it worked and got power but no ground- I did switch bulbs- the airbag and the slow down to see if that would help. Maybe that caused the light issue with the airbag light?

WRT to the binnacle screws- they are quite long, i think you would have to be pretty unlucky to hit a wire and damage it though.

Thanks!!

 

Yeah, too good to be true. Even the F355 Workshop Manual says you can reset it by grounding a pin, but it has been disproven too many times with both types of F355 airbag ECU. Unfortunately, an SD1 tool is required for the reset. This tool will also identify the specific problem with the airbag system.

If you didn't apply ignition power to the car with the binnacle disconnected, it's hard to say what caused the airbag light. I don't have a wiring diagram for the airbag system, and I would be reluctant to start playing with the wiring in case of accidental discharge (even with the battery switch turned off). Some have said ohmmeters don't have the power in them to trigger the airbags, but others have said that their training and experience has shown/proved this not to be the case.