AEG E40 fault codewhat it means and how to fix it
The machine cannot confirm the door is properly shut, so it will not start. Usually the door, sometimes the seal, occasionally the latch itself.
Before you start
What E40 means
AEG put this one plainly: the code "indicates a problem with the proper closure of the appliance door. The tumble dryer will not start until the door is correctly locked." Nothing runs until the machine is satisfied the door is closed, which is sensible for a heated drum that spins.
Most of the time the machine is right and the door genuinely is not shut — a sleeve caught in the opening, a load pressing against the inside, or a door that has been pushed to rather than closed. The interesting part of AEG’s advice is what else they list.
Alongside checking the door, they suggest cleaning the door seal and cleaning or lubricating the door lock, and they name overloading as a cause in its own right. That last point catches people out: pack the drum tight enough and the load pushes the door out of alignment just enough for the catch to sit proud, so the machine reports a door fault when the real problem is how much you put in. This is one of the few codes in the range with no do-not-use warning attached, and rightly so — nothing here is dangerous, it is just a machine that will not start.
What causes it
| Cause | What is actually happening | How likely |
|---|---|---|
| The door is not actually closed | The most common answer and the one worth ruling out first. A dryer door needs a positive push until the catch clicks, and a door resting against the frame looks shut from across the kitchen. | Common |
| Washing is pressing against the door | AEG name overloading as a cause of this code. A tightly packed drum pushes the load against the inside of the door and holds the catch a fraction out of engagement, which is enough for the machine to refuse. | Common |
| Fluff or debris built up in the door seal | Cleaning the seal is one of AEG’s published checks. A ridge of compacted lint round the seal stops the door seating fully, with the same result as a load pushing on it. | Occasional |
| The latch or lock mechanism is worn or stiff | AEG suggest cleaning and lubricating the lock, which is unusual advice from a manufacturer and tells you they see mechanisms that stick rather than fail outright. A worn catch engages inconsistently and produces an intermittent fault. | Occasional |
| The door switch or its wiring has failed | When the mechanism latches properly but the machine still refuses, the switch that reports the state to the board is the remaining candidate. This is the version that needs a part rather than a clean. | Rare |
What to try yourself
Open the door fully and close it again with a deliberate push until you hear the catch engage. Do not rely on it looking shut.
If the drum is packed, take some washing out. AEG list overloading as a cause of this specific code, not just of poor drying.
Wipe round the door seal and the lip it closes against, clearing any ridge of compacted fluff.
Look at the catch on the door and the socket it goes into for anything caught in them, and check the catch is not bent or loose.
If AEG’s suggestion of lubricating the lock appeals, follow their wording: clear the mechanism with a soft brush or compressed air first, then use a lock grease — they give a food-grade lubricant as the example. Do not use a thin oil, which collects the lint that caused the problem.
Still refusing with an empty drum and a clean seal? Unplug for thirty seconds, try once more, and then book someone — the switch is not something to chase yourself.
Get a qualified appliance engineer to look at your AEG E40
We do not pass enquiries to a repair firm, so there is no form here. When you book a qualified appliance engineer, tell them the make, the model and the exact code or message on the display, and ask whether they carry parts for this make — that is what turns one visit into a repair rather than a quote.
What it costs to fix
Typical repair cost
£0–£140
Time on site
10 minutes
Free in most cases, since this usually turns out to be the door, the load or the seal. A door lock assembly with labour is the upper end, and AEG keep door locks in stock for at least ten years after a model is discontinued.
Typical UK prices including parts and labour, updated September 2026. Your quote may differ.
Own this appliance and had this code? . Nothing is published until a person has read it.
Related AEG fault codes
- E50Get it checkedAEG’s support site calls this a motor or software fault and sends you to an engineer. AEG’s own manual says it is usually just too much washing in the drum.Related: same brand
- E60Get it checkedThe dryer is not heating. AEG’s own page for this code is circular — it defines E60 by telling you the machine displays E60 — so here is what it actually covers.Related: same brand
- E20Get it checkedThe machine cannot get rid of the water it has collected. This is the one code AEG confirm has three faces — E20, C2, or two beeps and two flashes, depending on your display.Related: same brand
- E70Stop — call an engineerThe dryer has lost the ability to measure its own temperature. AEG tell you to unplug it for two hours and not to use it until it is fixed.Related: same brand
- Condenser lightGet it checkedNot a fault code but a maintenance reminder, and the most important one on the machine. The condenser is furring up with lint and AEG tell you not to run it like that.Related: same brand
- Water tank lightUsually simple to fixThe container holding the water taken out of your washing is full, so the machine has stopped. Designed behaviour rather than a fault — though it can light with an empty tank.Related: same brand
Own an AEG tumble dryer? Save it and its codes come first next time.
Related guides
Common questions about AEG E40
My machine shows CD rather than E40.
AEG describe CD as a problem with the door latch, which is the same territory. What they never publish is that CD and E40 are the same fault on different display generations, so we will not state it as fact. If your machine shows CD, follow the same practical checks but treat AEG’s CD article as the one that applies to your machine.
It started mid-cycle rather than at the beginning.
That points more towards the load shifting against the door as it tumbles, or a catch that engages but does not hold. Try the same cycle with half the load: if it completes, the door is marginal rather than broken and the seal and catch are worth looking at.
Is it safe to run with the door slightly open?
You cannot, and you should not try to defeat the switch. The interlock is what stops a heated drum turning with the door open, and there is no version of bypassing it that is a good idea in a machine full of dry lint.
Technical review
Not reviewed by an engineer
No engineer has read this page. Severity follows what the manufacturer publishes, and we would rather tell you that than let a byline imply a sign-off.
Sources and how we verified this
We establish the facts from the sources below and then write the explanation ourselves. We do not copy manufacturer wording and we do not host their manuals.
- Manufacturer support portal
This page has not been reviewed by an engineer, and we would rather tell you that than imply otherwise. The severity rating follows what the manufacturer publishes: where they say isolate the appliance and call someone, so do we.