Verdeck steuergerät reparieren DIY

[Lucian_kel]

Hello everyone, my name is Luciano and I live in north Italy. I have a Audi Cabriolet model '94 and everything works great. 
The problem is with another Audi Cabriolet from '97, who bought it a friend of mine. At the beginning the top was not functional (he bought the car like this) but the previous owner gives him a second control unit for the top.
When I sow the trunk wiring, I decided to change it with a new one, and after that the top starts to work....but is not working properly. Is like the process of opening is not in the right order. After the first step (when the top is opened at maximum) the lid is pushed out by the piston, without unblock the 2 side "clamps". 
Yes, until now we can say that maybe the 2 side clamps is not functional. But when I try to close the top, the lid is opening at maximum. After that, is nothing happens, I have to close manually. 
I decided to check the control unit, and being the same pump with 8 cylinder, I put on the control unit from my car.
And in that moment I sow that the control unit from my friend car has an "A" at the end of the code. 
With my control unit the top is opening and closing normal, like should do.
The conclusion: the previous owner tried to change the control unit, but instead to put the right one 8G0 959 255, he putted the 8G0 959 255 A, the 6 cylinder pump control unit. 
I checked the control unit which the previous owner gives with the car, and is the right one, without A, but unfortunately is not functional. 
I sow that the prices is 4 times higher than the one with A....
My question is: did someone tried to repair a top control unit? Has someone idea what can be broken, maybe is repairable....
I read some old posts here on the forum, and link with a few places where can be repaired. I think that this is the right decision, if the price is under the 300-400€, like a used control unit from the ebay. At least, they will give a warranty for the repair.
Thanks all for attention, and excuse me for grammatical errors ?.

[Lucian_kel]

I read this day's some topics here and it's clear...the control unit is not that easy to work on. I started to repair the cruise control units from old Mercedes, like w123, w126, R107..., and it's not that complicated. I even built a bench test to check the functionality and it's working very well.
Inside the amplifier (control unit) some capacitors are dry and is easy to be changed, some soldering to motherboard and it's ready.
I tried to open the roof control unit from Audi and ... all components are newer, smaller and with higher complexity. Nothing to do.... I tried to soldering all connection from the circuit, but without any result.
Is not that easy like I thought, but I'm sure that if someone with more knowledge in electronics will dedicate a little more time, can easily repair this control unit. At the end, being so many from old generations (without A), I suppose that the problem is has to be the same for all. Definitely is some cheap electronic parts for which the costs is a few euros.
I have some non functional control unit and I will try to change some components. I will post here if I have some good results.
best regards
Luciano

[Lord of the Rings]

Dear Luciano,

It ist crucial to use matching partnumbers.
Your pictures show different ones.

8G0 959 255 and 8G0 959 255 A

The difference is Index A and that makes all the difference.

We have two dealers listed who could provide you with used parts upon availability

www.Autewo.de Autoteile Wolf
www.mn-fahrzeugteile.de/ Marco Nikolic

Cheers,

Michael

[Lucian_kel]

Thank you for answering Michael. I know that there is two different types of control unit, without "A", which is more expensive and rare, for 8 coil pump and with "A", for 6 coil pump.
I need one without the "A" for my '94 cabrio. Already I bought one from Holland, but the seller was not serious and sell it to me a bad one, without function... I'm scared and I will not buy anymore from someone who can give me a warranty.
I was thinking that maybe someone here found a source where this control unit (without A) can be repaired.
Best regards
A. Luciano

[Lucian_kel]

Hello everyone. At the end, was easier to find some control unit without "A". I was fortunate and all is fully functional, and I'm very happy for that. In the end, the seller which in the first time send it to me a bad control unit, resented another control unit, this time a functional one. In total I have 4 functuonal control unit without "A". One will be installed on my car, and three of them will be well keep it, because how my friend says, "in the future can be weight up in gold".
I wish you all a nice spring time.

[lemmy]

Buona Sera

so in the end we may call you "Lucky Luciano"!
Have lots of fun with your now repaired car!

[Lucian_kel]

Yes Lemmy, this time I really was "Lucky Luciano". After seeing all the problems that this control unit can make, was a real fortune to find 4 of them, and all functional. 
Thank you, I will definitely enjoy again my beautiful convertible. 

PS I can't upload any photos, I receive the following message: 

"  Please correct the following errors before proceeding:

[*]Sorry, you cannot post this attachment because your 9.77 MB disk space is full."

Is there something that I have to do? Thanks.