Miele Dishwasher Error Code F12

F12 is a water intake fault that appears when the dishwasher's flow meter does not register at least 15 pulses within the first 5 seconds of a water intake step. This tells the control board that water is not flowing into the machine at the required rate. The machine stops the cycle to prevent running without adequate water. The most common cause is a closed water supply shutoff valve.

Resetting the dishwasher may clear the displayed error temporarily, but the fault will return as soon as the machine attempts another fill cycle if the underlying problem has not been fixed. A reset is only useful to confirm whether the issue is resolved after you have addressed the root cause. The F12 condition is based on real-time flow meter readings, so the control board will detect the fault again immediately if water flow is still inadequate.

If the fix is simply opening the shutoff valve or straightening a kinked hose, there is no parts cost involved. Cleaning a clogged inlet valve screen is also typically a no-cost repair. If the water inlet solenoid valve needs replacement, parts and labor can range from roughly 100 to 250 dollars depending on your location and service provider. Replacing the flow meter sensor B3-4 can carry a similar or somewhat higher cost given the complexity of accessing the component.

Start by confirming the water supply shutoff valve is fully open and that the inlet hose is not kinked or pinched. Next, check the filter screen inside the inlet valve fitting for clogs and clean it if needed. If those steps do not resolve the error, the water inlet solenoid valve or the flow meter sensor B3-4 may need to be tested and replaced by a qualified technician.

You should not attempt to run a wash cycle while F12 is active. The dishwasher has halted the program precisely because water is not entering correctly, and running the machine without adequate water supply can stress the pump and heating element. Address the water supply issue before restarting the appliance.