Washing Machine
E40
The E40 error code on an AEG washing machine indicates a problem with the door — specifically, the machine believes the door is not properly closed or locked. It’s one of the most common AEG fault codes and is often straightforward to resolve yourself.
What does this error mean?
The E40 code means the washing machine’s control board is not receiving a confirmed signal from the door interlock (door latch mechanism) that the door is securely shut. Without this confirmation, the machine refuses to start or continue a cycle as a safety precaution. The fault can originate from the door latch itself, the wiring connecting it, or the interlock switch that sends the signal.
Est. repair cost
£80–£130 for professional repair; £15–£35 DIY door interlock part
🔍 Likely causes
🛠️ Step-by-step fix
Reset the machine: Switch the washing machine off at the mains, wait 2 minutes, then switch it back on and try restarting the cycle. A temporary glitch can trigger E40.
Check the door seal and drum: Open the door and check nothing is caught between the door and the rubber gasket. Remove any laundry, then firmly close the door — you should hear a distinct click as it locks.
Inspect the door handle: Look for cracks or a broken mechanism in the door handle. If the handle feels loose or doesn’t engage, it may need replacing. AEG door handles typically cost £10–£25 and are DIY-replaceable with a screwdriver.
Examine the door interlock: With the machine unplugged, inspect the door latch area for visible damage or a burnt smell. If the plastic is cracked or the lock no longer clicks, the interlock needs replacing — a common DIY repair using a compatible AEG spare part.
Check door alignment: Look at whether the door sits flush with the machine body. If a hinge is sagging, the door won’t engage the latch cleanly. Tighten hinge screws if accessible, or call an engineer for a hinge replacement.
If the above steps don’t resolve E40, do not attempt to open the control panel or probe wiring yourself — call an AEG-approved or independent appliance engineer at this point.
📞 When to call a professional
Call an engineer if the error persists after checking the door, seal, and handle, or if you suspect a wiring or control board fault. Tell them you have an AEG washing machine displaying error code E40 and that the door interlock has already been visually checked. Touching wiring or the PCB without the correct knowledge is not safe and should be left to a qualified appliance technician.
⚖️ Repair or replace?
A door interlock replacement by a professional typically costs £80–£130 including parts and labour in the UK. If your machine is under 7 years old and otherwise in good working order, repair is almost always the better value. If the machine is over 8–10 years old and has had previous faults, a new mid-range AEG or equivalent washing machine (from around £400–£600) may be a smarter long-term investment.