[Solved] Siemens EQ.7 TE706209RW / 14 Coffee Machine: No Water Flow from Nozzles, Milk Frother Issues

Hello,
I have a problem with the Siemens EQ. 7. It's probably clogged up somewhere. symptoms:
1. After turning the coffee machine on (power on), no water comes out of the coffee nozzles. When the machine was operational, it rinsed the nozzles.
2. After activating the milk frother cleaning, it carries out the first cycle (pouring water in with the small nozzles on the side) and then finishes cleaning without any message. The amount of water poured in is probably less than when it was operational.
3. When the program has started: hot water, milk, milk foam, nothing flows.
4. During these operations, water flows into the drip tray. It is difficult for me to determine if in all cases.

Every time you hear that the pump is running. The diagnostic program can control the ceramic valve, all steps (0..8) are completed.
I also suspect a flow meter. When I turn on the pump with the diagnostic program for a few seconds, the amount of ml on the display does not change (0 ml all the time), even though water flows out of the milk frother. If someone has a similar coffee maker, I would ask you to compare if it is the same. I would then exclude the flow meter.
Please help.

Added after 5 [hours] 3 [minutes]:

Does anyone know how to check the flow meter (at first without disassembling the coffee machine and the flow meter) using the SDS (Service Diagnostic System) diagnostic program? The display shows 0ml - probably the amount of water that flows through it is being counted. As a reminder, in the EQ.7, SDS is turned on by holding the leftmost and rightmost buttons and then "power on".

Hello!
Contamination tends to settle down!
Buy a cleaner!
Water stone release!

Hi varga janos,
thank you for response. I have tried to clean my device twice but it has been very strange, normally the cleaning lasted about 30 minutes, now only several minutes, without results. What about the flowmetter? When I measure a voltage on the flowmetr's pins during running the pump, the voltage changes from 4,7V to 2.5 V but on the display is still 0ml (SDS test).
Before, I repaired a circuit board and my coffee machine was unused for 4 weeks and it is possible that stone is the reason.

Hello!
Did you measure oscilloscope?

No, only by multimeter. First I will try to clean once more. Next I will have to pull the oscilloscope out of my cellar (It was used over a dozen years ago, now I work as software engineer). I see that you are high skilled. Have you got schematic diagram of EQ0.7 (lower circuit board)? What is the meaning of flowmetter's pins (red, green, white)?
Let me write you again when I have some information.
Best regards

Hello!
The flowmeter can be good. Nearly 50% of the fill factor coefficients are squared in the AC position with the multimeter to measure this. The measuring points are GND, 5Vdc and Signal ..Is not the distributor's plastic house buried? Because you can not fix it

Problem has been solved. The reason for the incorrect operation was the lack of pulses from the flow meter to the processor. The fault was the corrosion of the grommet connection (20180814_114256_001_1.jpg). Previously, the machine did not see the waste tray and there was no control of the brewing unit motor. The reason for the previous failures was the dropout of two resistors and the foot of the transistor (20180809_135952_1.jpg).
All caused by moisture droplets that got on the plate, it is poorly protected by the way. Electronics working in a humid environment should be covered with something (equipment for over PLN 4,000!).
Thank you for your help Varga Janos.

Unfortunately, I still have a problem with the milk frother (sucks milk / water too poorly).
Before my repairs, the frother was working properly. The frothing nozzles are clean, everything is blown out and washed and the machine has been descaled 2 times before (I attach a video).

Hello!
Bravo!

Does anyone have an idea what else I can check if the milk / water is sucked in by the foamer tube? It seems to me that the frother is tight and clean, I have been descaling many times in recent days (liquid and cubes). I am not sure if the amount of steam is sufficient to create a vacuum in the tube. Do you disassemble and check the ceramic valve?

Hello !
Can the steam path in the valve be interchangeable in both directions?
https://data.hu/get/11377125/Exploded_drawing.pdf

Hi Janos !
How can I check it? What does is mean the second direction of valve of steam?
Can I check it using SDS option?
It is possible to check a ceramic valve in SDS function.
CV1: Initialization - tray for dripping drops
CV2: Steam without air (for hot cream)
CV3: Expansion of steam (pressure reduction through
expansion chamber)
CV4: Hot water
CV5: Expansion of hot water (through the chamber
expansion)
CV6: Brewing
CV7: Expansion of the brewing unit (through the expansion chamber)
CV8: Steam with air (for creamy production
foam)
Have you written about it?
I have disassembled and cleaned the ceramic valve and pipes. No positive results.
Thank you for drawings.

Hello !
Pas!

Dodano po 4 [godziny] 49 [minuty]:

Hello
"The taste of pudding is eating, "says the British.
Try it!

Hello !
What was achieved?

Dodano po 2 [minuty]:

Hello !
Think about what you changed with the foaming machine? What did you change? (If there was a replacement.)

I have a request for those who have a similar machine: is there a gasket missing in the milk frother (photo), an element that could fall out during cleaning?
Could the pulsating (discontinuous) production of steam (film) be the reason why the milk is not puffing? I am sure that the frother is tight, additionally I replaced the seals on the steam nozzles

Success!
As I thought before there was too little steam. This model has two heaters 2x950W. One of these wasn't switched on (no control impulses of triac gate). It turned out that connection between circuit board layers was corroding (photo). My wife will be happy!
Thank Janos for interest and time.
I treat the topic as closed.

PS It is a pity that, apart from our Hungarian colleague, no one was interested in the topic, and I had to answer the questions myself. Maybe my experiences will be of some use to someone.

Hello!
Bravo!