Siemen TE501505DE/06 Error reading without display?

I have for some time a Siemens TE501505DE/06 or in short an old EQ5 without display.
Since this morning suddenly nothing goes or only the pump for the steam valve... After switching on only the LED for the water tank and the LED for the steam flashes. If I then pull the milk foam nozzle, the machine also pumps water through it. However, when it is finished, all 6 LEDs start flashing and nothing happens...
I would have at least like to read out an error code about flashing or the like but can find absolutely nothing on the Internet has there maybe someone a tip?
For the model with display I found a manual but not for the older model without display...
I hope that here is someone who can give me a tip