AEG dishwasher i40 error
Usable, but not working properly
The appliance cannot get a trustworthy reading of how much water is inside it, so it halts rather than guessing and either running dry or overfilling. The filters and the well beneath them are heavily fouled, which upsets the flow the level sensing depends on is the most common cause.
- Difficulty
- Some experience
- Time needed
- About 45 min
- Checks
- 6 steps
The same fault is shown as i41, i43, i44 on some AEG series, depending on the display and the model year.
Before you start
- Disconnect the appliance from the mains before reaching into the base, and beware of fragments of glass in the well beneath the filters.
- Descaler is acidic. Follow the dose on the packaging and keep it off your skin.
What it means
The appliance cannot get a trustworthy reading of how much water is inside it, so it halts rather than guessing and either running dry or overfilling.
Most likely causes
Ordered from most to least common, with what each one looks like:
| Cause | How likely | What you would see |
|---|---|---|
| The filters and the well beneath them are heavily fouled, which upsets the flow the level sensing depends on | high | The filters have gone a long while without a proper wash and feel greasy rather than merely dirty |
| Foam from excess detergent, or from washing-up liquid used by mistake, is confusing the reading | medium | Bubbles are sitting on the water in the base, or the dose was increased recently |
| The narrow chamber and hose the sensor reads through have silted up with scale and sludge | medium | The machine is in a hard water district and has never been descaled |
| The sensor or its wiring has failed and is reporting nonsense regardless of the water level | low | Everything reachable is spotless and the fault still appears on an empty rinse |
Fix steps
Tools needed
- Washing-up brush
- Cloth
- Torch
-
Isolate the appliance from the mains and let the tub cool if a hot programme has just ended.
Expected result It is safe to reach into the base and nothing can start unexpectedly.
-
Check whether foam is sitting on the water. If it is, ladle it away, wipe the tub and establish which product was used, because foam alone can cause this reading.
Expected result You know whether detergent is the culprit before dismantling anything. If it does not, go to step 3.
-
Withdraw the filters, scrub both parts in hot water with a brush and a little detergent to shift set grease, not merely to rinse off scraps.
Expected result Water passes through the mesh without hesitating anywhere across its surface.
-
Clear the well the filters drop into, lifting out sludge and grit with a cloth so the base is genuinely clean rather than tidy.
Expected result The recess is free of deposits and nothing is sitting in the openings around it.
-
Lock the filters back in, restore power and run a hot programme empty with a proprietary descaler to shift scale from the internal passages.
Expected result The programme reaches its end and the reading settles. If it does not, go to step 6.
-
If the fault persists with everything reachable proven clean, book an engineer rather than repeating cycles, since the sensor sits behind the tub and is not a user-serviceable item.
Expected result The engineer arrives able to test the sensor and its loom, with the easy causes already eliminated.
Parts needed
| Part | Part number | Typical cost |
|---|---|---|
| Filter set | Varies by model | Varies by supplier |
| Dishwasher descaler | Varies by model | Varies by supplier |
When to call a technician
Call a qualified technician if you work through every step above and the code comes back, if you find water where it should not be, or if any part of the job needs the machine powered up with panels removed. A repeat fault after a correct repair usually points at the control board rather than the part you replaced.
Common questions
What does i40 mean on a AEG dishwasher?
The appliance cannot get a trustworthy reading of how much water is inside it, so it halts rather than guessing and either running dry or overfilling. The filters and the well beneath them are heavily fouled, which upsets the flow the level sensing depends on is the most common reason for it.
Can I keep using the dishwasher?
You can usually still run the machine, but it will not be working correctly and the fault will keep coming back until it is fixed.
Is this something I can fix myself?
Partly. The first checks are straightforward, but the later ones need washing-up brush, cloth and torch and some confidence taking panels off. Budget about 45 minutes.
Models this applies to
Related codes on the same machines
- i10 The machine asked for water and not enough arrived, so it stopped rather than starting a wash with an empty tub.
- i20 The machine has tried to empty itself and the water has not gone, so it has stopped with dirty water still standing in the base.
- i23 The cover that seals the drain pump is loose, fitted incorrectly, or missing altogether, so the pump cannot build suction and the water stays where it is.
- i24 Something solid has reached the drain pump and is stopping the impeller turning.
- i30 The anti-flood device in the base of the machine has been triggered by water where there should not be any.
- i50 The motor that drives water up to the spray arms is not behaving as the control board expects, so the wash is abandoned.
Sources
- Electrolux Group (AEG), AEG support, dishwasher error codes i40, i43 and i44 (link) — retrieved 2026-07-26