Dishwasher Medium Severity
F12 Miele Error Code

Water Intake Fault

The F12 error code indicates your Miele dishwasher is not receiving enough water. The control board has detected that the tub did not fill to the required level within the allowed time, or the water flow rate is below the expected threshold.

~55%

DIY Fixable

$100-300

Typical Repair Cost

30 min – 1 hr

Pro Repair Time

Quick Assessment

Answer to continue safely

Is it safe to keep using?

No. Running the dishwasher without adequate water can damage the wash pump (running dry) and will not clean dishes properly. Resolve F12 before starting a new cycle.

Can I reset the code?

Yes. Yes. Turn off at mains for 5 minutes. But the reset only clears the display — if the water supply is still restricted, the code will return.

When to stop immediately?

Stop if you notice: The tub does not fill at all after verifying the tap is open, You hear buzzing from the inlet valve but no water enters.

Symptoms You May Notice

Cycle does not start properly

The dishwasher attempts to fill but stops or pauses early in the program

Very little water inside the tub

Opening the door reveals the tub is nearly empty or water barely covers the filters

Wash results are poor

If the machine runs with insufficient water, dishes come out dirty with detergent residue

Clicking sound from the inlet valve

The solenoid valve may click rapidly as it tries to open and close against low pressure

Possible Causes

1

Water Supply Tap Closed or Partially Closed

The shut-off valve feeding the dishwasher is not fully open, restricting flow. This is the #1 cause (~40% of cases).

DIY Possible
2

Kinked or Blocked Inlet Hose

The braided or rubber inlet hose is bent, crushed, or has sediment buildup inside, reducing water flow.

DIY Possible
3

Clogged Inlet Filter Screen

A small mesh filter sits where the inlet hose connects to the dishwasher. Mineral deposits or debris can block it over time.

DIY Possible
4

Faulty Inlet Valve (Solenoid)

The electromagnetic valve that controls water entry has failed electrically or is stuck closed.

Requires Professional
5

Low Household Water Pressure

If your home water pressure is below ~0.5 bar (7 psi), the dishwasher may not fill fast enough. This can happen when multiple fixtures run simultaneously.

DIY Possible

Safe Checks You Can Do

These checks are safe for homeowners. No disassembly required. Do not remove panels or access internal components.
  1. 1

    Check the Water Supply Tap

    Locate the shut-off valve under the sink that feeds the dishwasher. Turn it fully counterclockwise to ensure it is completely open.

    After plumbing work or moving the machine, this valve is often left partially closed.

  2. 2

    Inspect the Inlet Hose

    Pull the machine out carefully. Check the hose from the tap to the machine for kinks, tight bends, or visible damage. Straighten any sharp bends.

    The hose should have a gentle curve — no sharp angles within 10 cm of either end.

  3. 3

    Clean the Inlet Filter Screen

    Turn off the water supply. Unscrew the inlet hose from the back of the dishwasher. You will see a small mesh filter inside the connection. Remove it carefully with pliers, rinse under running water, and refit.

    In hard-water areas, soak the filter in white vinegar for 15 minutes to dissolve mineral deposits.

    Tools required
  4. 4

    Test Household Water Pressure

    Run the kitchen tap fully while no other fixtures are in use. If the flow is noticeably weak, the problem may be low mains pressure or a partially closed main valve.

    Try running the dishwasher at a time when no other appliances (washing machine, sprinklers) are using water.

  5. 5

    Power Reset

    Turn off the dishwasher at the mains for 5 minutes. Turn it back on and start a new cycle. Monitor whether the tub fills normally.

    If the tub fills but slowly, the issue is restricted flow rather than a valve failure.

When to Call a Professional

Contact a qualified Miele technician if:

  • Inlet valve buzzes but no water flows — valve likely failed
  • F12 persists after confirming full water supply and clean filter
  • Water pressure at the tap is normal but the machine does not fill
  • The AquaStop hose indicator shows red (hose has triggered)
  • The machine is under warranty

Need Professional Help?

Find qualified Miele technicians in your area for proper diagnostics and repair.

Schedule Appointment

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