What this error means
Pressure system fault — the water level sensor is not reading correctly
The E04 error means the pressure sensor has returned a reading outside the expected range or has stopped responding. This is most commonly caused by a blocked or kinked pressure hose, detergent residue inside the hose or sensor chamber, or a failed pressure sensor. If left unresolved this fault can lead to the machine overfilling.
What you'll need first
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Step-by-step
Symptoms to look for
- Machine fills then pauses for an unusually long time before tumbling begins
- Drum appears to fill beyond the normal level — water visible high in the door glass
- Programme stops during the fill phase with E04 displayed
- Machine fills normally on some cycles and overfills or underfills on others
Diagnostic steps
Unplug the machine and hold the programme selector for 10 seconds to discharge the control board. Leave unplugged for 60 seconds. Plug back in and run a 40-degree programme.
Place a spirit level on top of the machine and check in both directions. Adjust all four feet until completely stable with no rocking. Tighten each locking nut against the machine base.
With the machine unplugged, remove the top panel by undoing the two rear screws. The pressure hose is a narrow tube running from a stub on the outer drum body up to the pressure sensor — a small cylindrical component with an electrical connector and the hose on its lower port. Check the full length for kinks, cracks, splits, or disconnection.
Disconnect the hose from both the drum stub and the pressure sensor. Blow gently through the full length — airflow should be completely unobstructed. If restricted, flush with warm water and dry fully before refitting. Clear the drum stub with a cotton bud if blocked with hardened detergent.
With the hose disconnected and the wiring connector removed, test across the sensor terminals with a multimeter. Blow gently into the hose port — the resistance should change as pressure increases. A sensor that reads open circuit in all states has failed.
Push the pressure hose firmly onto both stubs. Replace the top panel. Run a 40-degree programme and observe the fill — it should stabilise at normal level before tumbling begins.
When to call an engineer
- Pressure hose is cracked, split, or has collapsed internally
- Pressure sensor reads open circuit across all terminal combinations
- Machine overfills even after the pressure hose has been cleared
- Control board relay stuck in the closed position — continuously energising the inlet valve
Frequently asked questions
What does the pressure sensor do?
Can a blocked pressure hose cause the machine to overfill?
Is E04 dangerous?
Can I clear the pressure hose myself?
🎯 What is likely causing this fault?
⚠️ Estimates based on common faults — not a guaranteed diagnosis. Always verify before ordering parts.
Parts you may need
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Usually found on a label inside the door frame or on the back panel of the machine.
| Part | Approx. UK Cost | Find it |
|---|---|---|
| Pressure switch | £10 - £22 | 🛒 Amazon UK → |
| Pressure switch | £12 - £20 | 🏷️ eBay UK → |
ℹ️ Prices are approximate. Always check the part number matches your model before ordering. Not sure of your model number? Find out how to locate it here.