Krups EA826E - no water in brewing unit

Dear coffee machine professionals,

I have already read a few articles here with great interest, but unfortunately I can't get any further now and maybe someone has the crucial hint for me.

My machine (Krups EA826E10) ran perfectly so far (bought 2016, so far >6000 coffee according to service menu).

Suddenly no more coffee came out, but everything landed in the drip tray. After a short research this probably indicates the drainage valve.

So everything disassembled, but before I really wanted to disassemble the drain valve, I first wanted to let the machine run disassembled, just out of interest and maybe to understand more. Unfortunately, this has now thrown me quite behind. First it came into a loop of water circuit fill / autotest etc. But now it always ends with the red protection compartment being removed, but it hooks, because the brewing piston does not rise any more.

Then I looked in the service menu, whether one can control the pump here (with some machines one can drive the water supply into the basic position by a corresponding menu option). But I can't find this point on my machine (there is Informations, Heating, Autotest, Grinder, Calibration, but nothing with pump or water cycle or similar).

Hence my question: What should I do best now? Does it make any sense to remove the drainage valve and check / change it or is it obsolete for the time being because something else seems to be broken? Or could this even be connected? Or could it be repaired somewhere?

I am very inexperienced myself, but I like to try it out.

Thank you very much for reading, for your efforts and I am looking forward to your feedback.

Marc