all grey picture on Atik 4000

It might help if you post a picture of the issue that you're having.

I'm sure a picture of a grey screen is very informative…

andrea tasselli:
I'm sure a picture of a grey screen is very informative...

someone made millions by writing about 50 different shades of them.. So.. maybe..



Either way, your comment doesn't help much either.
There also is a "half grey" image. who knows.. perhaps someone can spot things.. sensor faults, reading faults or something else. Is there still noise? is there a gradient? it is just flat grey?.  I probably won't be able to get much out of it, but someone with better knowledge might do depending on what it looks like.
It perhaps would provide a better starting point than: "it's grey" 



You already have done the simple checks of trying a different computer. So at least that part of the "test" is done.

Did you try different software. NINA, APT, etc?  Might not make a difference.. but might rule out.. something?..
Did you try different exposure lengths? (probably won't make a difference, but still)
Did you try different cooling temperatures?
Did you try it using new cables?

Either way, can't find much on google about the issue. 
Doesn't help that googling "astrophotography" and "grey" usually just lists mono camera's..


the only issue I could find was this:

top being with a flashlight directed into the sensor.
bottom being a normal 20 seconds dark exposure

No idea if that is similar to what you are seeing. unfortunately the topic that had this comment in it, didn't come to an answer or solution.  So either way, it doesn't help much.

i have tryed many software with the same result

Frédéric Tapissier:
(simluation)
This is a simulation
the images were recording normally, but after a while one image appeared like this and the others were all gray

This looks like what happens when my camera loses connection to computer.

With SMDs is very difficult to tell and even more so removing the faulty one. To test if a capacitor is blown just measure the resistance. If it is always very low this would suggest a blown capcitor, as a fully functioning capacitor would slowly charge up thereby increasing its resistance.

Jérémie:
Salut @Frédéric Tapissier ,
When did you buy it and was it bought through an EU retailer (French, German etc...) ?
If that's less than 2 years, you can oblige them to replace it or repair it, provided it was used correctly :
https://europa.eu/youreurope/business/dealing-with-customers/consumer-contracts-guarantees/consumer-guarantees/index_fr.htm

Not sure that helps, but you may try... because paying 800 euros for faulty material, that's a bit unfair...

Sadly, no, I bought it used. It worked very well for several months before breaking down. In addition this camera was designed about fifteen years ago I would say

Christophe Perroud:
As-tu essayé de remplacer le câble USB? Ou peut-être la prise de la caméra a un défaut au niveau des contacteurs?

oui J’ai changé le câble USB. Je travaille dans le support informatique, j’ai l’habitude d’effectuer des tests croisés
Yes, I changed the USB cable. I work in IT support, I'm used to cross-testing