PMM Fagor LF-013S Error 9 beeps ⇐ Fagor

[max. Polonets]

Good afternoon, ladies and gentlemen. I searched the entire Internet, but have not yet been able to figure out the problem on my own. Therefore, I ask for help. I myself am not an expert in dishwashers.
The problem is this:
The Fagor LF-013S PPMM stops during washing and gives an error of 9 beeps. According to the manual, this means Alternative.
After googling, I found a couple of videos about this error.



etc.
All of them indicate a lack of contact on the limit switch indicating the position of the distributor valve.
I disassembled the valve, indeed the contact groups were very dirty, cleaned everything, reassembled it, but this did not bring any results. The error remains.
I dug up the service manual for this machine. The link does not allow posting, but is easy to Google.
According to it, the controller learns about the position of the valve, the time the limit switch is in the closed state.
According to the cyclogram, the valve has two states DS2 and C, the first when filling and emptying with water, the second is during the washing process, as I understand it.
An error in the Eco program appears after about 40 minutes, because... According to the cyclogram, both the DS2 and C cycles are successful.
The motor is working, it supplied 220V from the socket, the engine is spinning, the limit switch is ringing.
Hence the question. What can generate the 9 beeps (Alternative) error? And where to dig?