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Alfa GT - driver's window short drop/rise problem

7K views 27 replies 7 participants last post by  boneman147 
#1 · (Edited)
Alfa GT - driver's window short drop/rise problem - Solved

Usual windows short drop of few millimeters (door opening) and rise (door closing) disappeared.
All other functions on driver side are OK: manual drop/rise of window, lower door warning light, dashboard warning of open door and locking/unlocking. Problem is only on driver side. On the passenger side - all is OK.
Btw... sometimes characteristic sounds (like non-stop locking/unlocking) come from driver's door.

What are ideas about source of problem?
 
#2 ·
Have done the standard window reset?

Open the window and keep the window switch pressed down for ten seconds.

then

Close the window and keep the window switch lifted up for ten seconds.
 
#3 ·
I tried this, but without success.
Maybe system doesn't recognise that window is in top position and because of this short drop (and rise) isn't possible. It is well known that short drop appears only if window is in calibrated (10 seconds procedure) top position.
 
#4 ·
I have two ideas about source of problem:
a) simple - some mechanical failure which disable possibility of short drop and short rise
b) complicated - failure of Hall positioning sensor (located in window's motor) what make "10 sec" calibration impossible.
If this positioning sensor is in failure state body comp can't determine top position of window and because of this short drop is impossible, because short drop/rise will not be realized if window is in some other position or in some wrong determined other position.
 
#6 ·
I've spent quite some time working through all the usual series of issues with my GT's driver window. And I've come to the conclusion that all of my problems came from a poor electrical contact caused by corrosion in one of the connector blocks to the window ecu (that is the black box inside the door card with two connector blocks). My issue is with a permanent live connection inside the white plug. For a couple of years I could get the faults to temporarily go away by removing and re-inserting that plug. I also used to try to clean problem terminal, this would also help. Now though the contact is far too rotten to get any improvement, I'm in process of sourcing materials to attempt to fix the plug internally.

Your issue may be something else - but my advice is to check that plug out.
 
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#7 · (Edited)
For a couple of years I could get the faults to temporarily go away by removing and re-inserting that plug. I also used to try to clean problem terminal, this would also help.
Your issue may be something else - but my advice is to check that plug out.
Thank you jonb.gt for your informative help... :thumbs:

Btw, it is possible that my problem has only mechanical source - few weeks ago when my window remained in top position during opening of door I could manually press window down in proper position for door opening state and after this all worked OK. But this "method" isn't valid now.
I suppose that windows ECU is device on the figure...
 

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#8 ·
Yes, that's the thing. The issue, for me, is the white block - more specifically - I'll bet if you looked inside the socket you'd see that the pin located on the bottom left of the group of six in the right hand segment is blackened. And the corresponding segment of the plug on the harness is corroding. My theory is that this poor/intermittent connection gives rise to all the issues coming and then going away randomly; allowing you to think to fault has been fixed or gone away.
 
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#10 ·
That looks like the one - all I know is it's the pin that has a permanent live running through it (I suppose that is why the windows can do their drop and close even with the ignition switched off). When it becomes corroded is when the trouble begins, imo. I suppose it's because there is always a live circuit in that connection that the reaction progresses.
 
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#12 ·
It is logical conclusion and this corroded contact could be bad for short lift/drop and not too bad for longer lift/drop of windows.

Had this problem with mine - turned out the door had dropped slightly on the hinge & this was causing it to fail when in the closed position (although still worked in the open position). Realignment of door required to fix it.
It is logical too... Skewed door causes skewing of window support and friction between window and guide elements could be enough for trouble.

Maybe I should to mention one more thing: my problems started after machine polishing of my GT in local workshop. Maybe vibrations caused by polish machine were source of disalignment of window in guides?
 
#14 ·
Today I established following: if driver's window is fully lifted, its foreground end (close to the mirror) can manually lift almost 10mm up, while foreground end of passenger side window stay in its fixed position.
It is probably case which is similar as that one described by MikeNeumann. I will see real state tomorrow after opening of door cover.
 
#15 ·
News: after removing of door's cover and checking of pins of door ECU connector I established that some of them were blacked. I cleaned these by use of fiberpen brush and special cleaning fluid for electrical contacts.
Unfortunately this didn't resolve problem. Opening and closing of this door is without short drop/rise of window and without any sound of electric motor.
All other things about this door is in proper function.
 
#18 ·
This micro-switch correctly detects open/close state of the driver's door: bottom door light is activated as well as "door is open" warning on dashboard screen.

Btw, do we see from the part of bottom attached electric scheme (eLearn) that only short drop by line 11 is activated by lock (N050) and door ECU (M116) while door's light and other are directly caused by open/close this microswitch in the lock.
eLearn says: "The doors open signal, used for the short drop function, reaches pin 11 of connector B of M116 or M117 from the locks N50 and N51 (these are the same signals that light up the timed lights )."


Did you disconnect the battery before you cleaned the contacts?
Is it necessary for protection reasons or...?
 

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#19 · (Edited)
News again: all electrical contacts, wires and pins are checked... and all is OK.
In that case, sensor of window's vertical position (located in the electric motor of window mechanism) is only thing which remains as a source of problem.
If this sensor has problem window ECU can't to recognize top position of window and short drop isn't possible.
Because of this I ordered one used window mechanism with electric motor from local scrap.
We will see what will be result of this "window short drop saga"... :biglaugh:
 
#20 ·
Problem finally solved!
Source of problem was in the lock, most probably in the micro-switch which signalize open/closed state of door.
Micro-switch was in function only for courtesy door light and warning on dashboard screen, but didn't for short drop/rise of window.
After replacement of lock all three things are OK.
It will be very useful if someone has idea and explain for us why micro-switch worked only partially.
 
#23 ·
Btw, good idea is that try to disconnect probably failed lock in driver's door and connect some external lock because of diagnostic reasons. I bought both locks from local scrap shop.
For example, it can be used lock from passenger's door which should be connected on system of driver's door by one longer multi-wire cable. Many suppositions about source of problem could be proved or rejected in that way.
Finally, thanks for all suggestions were helpful in this issue!
 
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