Siemens EQ series Water in the drip tray - not coffee

Introduzione

It may be that only clear water ends up in the drip tray, but no coffee is produced. Two possible causes are shown here.

Note: you can also carry out the test in steps 7 to 9 without opening the appliance. Simply skip steps 1 to 6 first .

Unscrew the two Torx T10 screws at the top of the right side panel.
Some models do not have these screws. Then the side parts are only held by catches, some of which clamp very strongly. You may have to detach the back part first.

Lay the machine on its side with the water tank side facing up.
The side panel is essentially held on the ground by five strong catches. Pry up the pegs with a strong prying tool. It's pretty difficult and you need a lot of strength.
If the catches are loose, you can pull the side panel away from below. But it's still stuck in other places.
Use a plastic tool to pry the top cover up a few millimeters and lift off the side panel. Most of the time it's still stuck, especially at the front edge, you have to pull hard.

You may need to pry the front edge with a plastic tool.
Lift the side panel off, but don't remove it completely yet. It is still connected with a silicone tube.
The water tank lid is located at the top of the side panel. Lift it up off the hinges.

Pull off the silicone hose that leads to the water connection of the tank from the inside.

First check whether the water is dripping into the drip tray via the expansion vessel. To see this, you need to trick a sensor:
Make an L-shaped strip of cardboard about 5 cm long.
Slide the strip into the L-shaped opening at the top left of the drawer for the trester drawer. You should hear the microswitch click, the machine now "thinks" that the drawer is inserted correctly.
Insert an absorbent cloth in place of the drawer.

If you have already removed the left side, you will also have to trick the water level sensor:
Stick a small, not too strong magnet (this one is from a box top) on a strip of tape.
Attach the magnet over the two sensors so that the machine "thinks" there is enough water.

Switch on the machine and wait until it starts rinsing.
Observe whether a steady stream of water runs into your cloth. At most, a few drops should come out here.
In this case, the water runs out via the expansion tank. There are two valves that lead to the expansion vessel, either of which may be defective.
The left hose comes from the pulsation damper/pressure relief valve
The right hose comes from the ceramic valve

Start with the pulsation damper/pressure relief valve:
The valve is screwed on directly above the pump.
Remove the left hose from the expansion vessel and place its end in a glass of water.
Start the machine. If the water now runs into the glass, you have found the culprit: The pressure relief valve. A clogged heater may also be a possibility.
You can test the heater by also disconnecting the hose between the heater and the ceramic valve on the valve. Blow into the heater. It should go fairly easily.
If the water does not run into the glass, the pressure relief valve is probably OK. If the heater is continuous, the culprit must be the ceramic valve. Here are the instructions for the EQ5 and the EQ6.