Jura F50, does not brew coffee

Hello, I have here an F50 where I have replaced all the seals of the brew group and cleaned the grinder. After reassembly, the machine behaves like this. After switching on I should open the tap. Then the system rinses half a cup and I close the tap again. Then it heats up. Then I am supposed to press the maintenance button and it only rinses briefly from the spout. Now it is ready. I press the coffee button, it grinds coffee, the machine starts brewing but stops after 2/3 seconds. There is maybe half an espresso in the cup. I have checked the brew group for sure 5 times if everything is right, always the same result. Now I got myself a new brew group, but nothing has changed. When it is done with the short brew, it immediately asks me to open the tap. The pomace is also pretty wet. Does anyone know what it could be?
VG

Sounds like too little powder. If too little powder is ground, the brewing process stops.
Make a second cup. The powder chamber of the brewing unit should fill to about 4/5.

Hello Schlawi, I have just checked the connections on the flowmeter again. Top output to the pump, bottom input from the tank, right? I also disconnected the hose at the pump inlet and connected the tank. Water comes out of the hose by itself. The pump seems to have been replaced by the previous owner, at least I see an 03/22.

Yes, that fits with the hoses. Have you opened the flowmeter and checked for contamination?

No, aber probier ich mal.

Is totally clean. I tried swapping the connections, but there was no difference. The pressure regulator at the pump outlet is a little wet. Could this possibly be the cause?

Already had defective diaphragm regulator.
Where does it get wet? From above (hose seal) or does it have a hole?

Hello, so the leak came from the top, from the hose seal. I have replaced this and now it runs. Madness what this small leak has for consequences. Thanks again for tips.
VG Frank

Ok, but that was certainly not the fault that the machine wants to be permanently vented.

2 coffees this morning, 2 now. Runs flawlessly. Put my EQ9 aside for now and continue testing the F50.