456 GTA - Windows not closing all the way up

Giulio,
Buon giorno e benvenuto al forum.

The two window issues you describe are usually caused by different faults. Failure to raise all the way is typically a sensor or ECU problem. The gap is typically caused by a worn bushing / pivot pin in the regulator mechanism. The latter is a straightforward fix. There’s a place called F1 Imports in Florida that fixes them. There’s a lot of info in the following thread:

https://www.ferrarichat.com/forum/threads/456-window-problem-update.397523/

The sensors and ECU can be straightforward as well, as long as you can find the parts. They’re starting to get scarce here in the US.

 

I’ve had these problems with my 456 GT and the Jag Shop in Portland Oregon was able to make it right. They fabricate the clips rather than trying to find replacements.
Rains here a lot too
Mike
Seattle

 

Happy new year,
I have been reviewing these threads for the past 1.5 yeras because i have a 1995 456. I bought this car from a dealer in San Francisco where it has lived for the past 24 years. I mention that fact because when I drove the car to my mechanic for a timing belt service last month, the passesger side window started to dance up and down. When i picked the car up on Thursday it no longer did so, instead the window does not drop the standard 20MM when you open the door.

TODAY: I tried the microswitch on the door latch, I tried to do a reset with the key from the passesnger side and the driver side ( the passenger window does not move at all)
I took the ECU out of the car and reinstalled it still no luck ( it is now sitting on my kitchen counter top... thank god I am devorced...)
So far no luck on the window drop, what next?

I have a friend who is Italian and is in Italy right now, he is going to reach out to his friend who works for Ferrari to see if they have an ECU hidden away.

Any thoughts gentlemen?

Mark T
1995 456 GT

 

The ECUs are inside the doors on the 456GT (non-M cars).

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Sometimes looking at the online parts manuals will help you locate these things:

See item 45

https://www.eurospares.co.uk/parts/ferrari/456-gt-gta/bodywork-lighting/doors-framework-and-coverings-31332

I'm not saying this is the cause of your problem, but.... it might be. Also, these units may either be very expensive or NLA

 

Sorry, I misread your message. Is the window working manually?

The ECU receives multiple inputs (from doorlock key barrel, exterior handle, interior handle, motor position feedback circuits, etc) to enable the window drop. Does the window drop when opening the door from the inside (doors unlocked)?

Does your mechanic have an SD1 tool to allow him to interrogate the window ECU?

 

Here's the basic wiring diagram from the Workshop Manual (no wire colours or plug pin numbers available)

https://www.dropbox.com/t/5htBgIdA8AyVvpl9

 

Thanks for responding, the window is not droping when you pull the handel on the inside or outside.
The window does opperate if you use either the passenger or driver side door switch, meaning it will go up and down but it will not drop the 20mm it is suppposed to

 

At least we know it's not a power issue. I guess there could be a sensor issue. i.e. the system has lost position data. The ECU cannot even relearn how to operate the window drop if it can't calculate the window movement.

I guess it wouldn't be easy to remove the driver's door ECU to interchange it with the (suspected) faulty one.

@franschman was having problems with his 456 windows. I can't remember if he resolved them. He posted these photos of the ECU internals.

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As you can see, they are pretty complicated. Did you open them up to look for water damage or anything obvious such as burnt circuit board tracks or components?

Last I heard, Bart (Franschman) was looking for a replacement driver IC for the circuit board.

 

If we got a pin out schematic of the ECU and inputs and outputs, I’m sure we could graft another module in. I want to try and use a Maserati window ECU. Im sure it could be done.


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That's the hard part... no one has a proper wiring diagram for the 456 (non-M cars). The 456M switched to a single Window ECU (handling both windows).

Do the Maserati's have two ECUs?

 

I just spoke with a friend who suggested that I give a good cleaning to the microswitches on the door latch. The Car spent 24 years in the San Francisco area and the ECU itself looks to be like new.

 

There are a few switches controlling the windows, but as Marlon says, check the switch near the door latch. I've been told that this is the one of the switches for the window on the non-M 456.

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The other switch near the door hinges is for interior lights. Not sure which one is for the instrument panel door open indication. Perhaps someone knows or can check this for us?

 

I will check when I get home. I thought it was the other way around, but it's been a while since I sorted out the windows on mine.

 

Hello all, happy new year!

I am still struggling with a window ecu which has, most likely as all other options seem to have dried out, a faulty processor.

To Marlon, have you double-checked that your problem is ecu related rather than switch/wiring related by exchanging ecus left and right? They are interchangeable, so if your problem moves to the other side then you know it's definitely the ecu.

Meanwhile, if anyone has an ecu unit lying around (even broken ones), please let me know.

 

I checked my 456, and the switch in the striker is the one that allows the window to close fully. If I trigger the switch with the door open, the window will go up. If I release it, it 'burps' down.

 

I didn't realise there was one in the striker.

Do you know which one controls the door open indications on the instrument panel?
Is there also a microswitch near the hinges?

On the M cars, there are multiple triggers for the windows (or at least ones which affect the logic).

 

I'm not aware of one near the hinges Ian, but the M may be different to mine. I'll check and see which switch controls the door ajar light on the dash. I didn't think to look at it when I was checking.

 

I see the one near the striker is for internal lights (according to Ratarossa):

@5:19

 

The small push button switch he clamps is the one for the interior lights, yes.
If you look below the switch at the striker, you’ll see a switch inside there. That’s the one for the window.


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Makes sense. The interior door handle is connected to the female part of the door latch by a cable, so pulling the interior door handle should unlatch the door and, I assume, hit that microswitch, lowering the windows.

The 456 WSM has the worst english when it comes to describing the window drop...

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I have no idea what this means:

"By unlocking the doors after an [outer] handle operation, the glass lowers ...."

Is the window being triggered by the handle?

Subsequent paragraphs in the text above suggest the door key also triggers the windows.

 

There are two microswitches in the door lock and one in the catch (this latter is activated by pulling the opening lever either from the inside or outside). The microswitch in the catch opens before releasing the door, so in theory the window drops an inch before the door opens. The switches at the lock are for the manual (with key) adjustment as the window motor is a stepper motor, without end switches. The ends of the window travel are defined by the procedure with the key, the computer 'knows' all positions in between from feedback from the motor.

It is actually a rather elegant system, it is just so bloody complicatedly executed.

Has anyone been able to pull the software from the processor or is it 'fused'?

 

So you're saying the key lock is just for calibration?

I don't understand why you have to hold the key in the unlock position (at the second notch) for 4 seconds.