Krups Orchestro FNF5

[FONT=Arial][SIZE=7]I am asking for help:
My fully automatic coffee maker was launched in Nov.2006 Since some time the following happens:"When I use the water tank and switch on the machine you can hear the brew group working and the LED jumps on the red LED no water.If I take out the tank and clean the connection between tank and machine with a cloth, it works again.

Since yesterday morning this measure does not help anymore.
I tried it with decalcification,but it fails at the test step press steam button.it does not react.

I tried it with cleaning:device switches on automatically in the memory function and shows LED red "no water"

I disassembled the machine, inside looks like new. No error visible.water from tank to flow valve to pump + diaphragm regulator present.
No leakage and no typical electronic odour was detected.

Is there any help from you?

Is there a water sensor that could be defective?

Please politely ask for support!!!

LG.