Washing Machine
E51
The E51 error code on an AEG washing machine indicates a fault with the motor control circuit — specifically a problem with the triac on the motor control board. It’s a moderately serious fault that will stop your machine from running and usually requires either a reset or professional repair.
What does this error mean?
E51 signals that the electronic control board has detected an abnormal current through the triac — the component that regulates power to the drum motor. In plain English, the board thinks the motor is being driven incorrectly, either because the triac itself has failed, the motor has a fault, or there’s a wiring issue between the two. The machine locks out to prevent further electrical damage.
Est. repair cost
£10–£20 DIY (carbon brushes); £80–£160 professional repair (PCB triac repair or motor replacement)
🔍 Likely causes
🛠️ Step-by-step fix
Perform a hard reset first: switch the machine off at the plug, wait 5 full minutes, then power back on and run a short cycle. A power surge can trigger E51 without any component failure.
Check the motor brushes (brushed motor models only): unplug the machine, remove the back panel (two to four screws), and locate the motor. Carbon brushes shorter than 5mm are worn and need replacing — brushes cost £10–£20 and are a straightforward DIY swap.
Inspect the motor wiring: with the machine unplugged and back panel removed, trace the wiring from the control board down to the motor. Look for burnt, frayed, or disconnected connectors and reseat any loose plugs firmly.
Check the motor connector terminals for corrosion: a small amount of electrical contact cleaner on a cotton bud can clean corroded pins — reseat the connector and test.
If brushes and wiring look fine, the fault is most likely the triac on the PCB or the motor itself — do NOT attempt to open the control board or test live components. Stop here and call an engineer.
If the error returns immediately after a reset and you cannot identify a visible wiring or brush issue, book a repair — continued attempts to run the machine risk damaging the motor or board further.
📞 When to call a professional
Call an appliance engineer if the E51 code returns after a hard reset and the motor brushes and wiring connections look intact. Tell the engineer ‘my AEG washing machine is displaying E51, which I understand relates to a motor triac fault’ — this helps them arrive prepared with the right parts. Any work involving the control board or motor replacement must be carried out by a qualified engineer.
⚖️ Repair or replace?
A professional repair for E51 typically costs £80–£160 depending on whether the fix is a brush replacement, wiring repair, or full PCB or motor swap. If your AEG machine is under 7 years old and was a mid-to-high-range model (over £400 new), repair is almost always worth it. If it’s over 10 years old or a budget model, a new machine starting from around £350 may be the more economical long-term choice.