Dishwasher
E6
The E6 error code on a Siemens dishwasher indicates a fault with the aqua sensor — the component that measures how dirty the water is during a wash cycle. It’s a moderately serious fault that will prevent your machine from completing cycles efficiently, but in many cases it’s something you can resolve at home without an engineer.
What does this error mean?
The aqua sensor (also called the turbidity sensor) sits in the sump area of your dishwasher and monitors water clarity to automatically adjust the wash programme. When the machine displays E6, it has detected that this sensor is either not responding correctly or is sending readings outside the expected range. This typically means your dishwasher cannot gauge water dirtiness, so it defaults to a fault state rather than risk a poor wash result.
Est. repair cost
£80–£150 professional repair; £15–£40 DIY aqua sensor part if self-replacing
🔍 Likely causes
🛠️ Step-by-step fix
Reset the machine first: switch it off at the mains, wait 60 seconds, then switch back on and start a short cycle. A temporary sensor glitch will often clear with a hard reset.
Clean the filters: remove the coarse mesh filter and fine cylindrical filter from the base of the dishwasher tub, rinse under warm water, and scrub gently with a soft brush. Refit firmly before testing.
Clean the aqua sensor: locate the sensor in the sump area at the bottom of the machine (a small optical window, usually near the filter housing). Wipe the sensor lens carefully with a damp cloth to remove grease, limescale, or detergent film. Do not use abrasive pads.
Run a hot maintenance wash: add a dishwasher cleaner (e.g. Finish Machine Cleaner) and run the hottest programme empty. This helps dissolve residue affecting sensor accuracy.
Check your detergent: switch to a quality dishwasher tablet (not washing-up liquid) and ensure you’re not overfilling the dispenser. Run a cycle and check whether the E6 clears.
If the error persists after all the above steps, the aqua sensor likely needs replacing — this involves accessing the sump, which is a straightforward but hands-on repair. Order a genuine Siemens-compatible aqua sensor (part numbers vary by model — check your model number on the door frame) and follow your model’s service guide, or call an engineer.
📞 When to call a professional
If you’ve cleaned the sensor and filters, reset the machine, and the E6 code returns within a few cycles, call a Siemens-approved appliance engineer. Tell them: ‘My Siemens dishwasher is displaying error code E6 — I’ve cleaned the aqua sensor and filters and suspect the sensor or wiring harness needs replacement.’ If the fault points to the main PCB, professional diagnosis is essential as board replacement is costly and needs to be confirmed before spending money on parts.
⚖️ Repair or replace?
A professional repair for an E6 fault — typically sensor replacement plus labour — costs around £80–£150 in the UK. If your Siemens dishwasher is under 7 years old, repair is almost always the better value. For machines 8 years or older, weigh the repair cost against a new mid-range dishwasher (£400–£600), especially if this isn’t the first fault — replacement starts to make financial sense.