Problem summary
If your Samsung WW90 washing machine door won't close properly, the machine will not start a cycle. The door may sit ajar, or close but not latch firmly. This is a safety feature — the machine detects an open door and prevents operation to avoid water leaks and injury.
Likely causes
Based on common faults in the WW90 range, the most likely causes are:
Door seal (30% of reported cases) – The rubber gasket around the door edge can tear, harden, or come dislodged over time. A damaged seal prevents the door from closing flush, breaking the latch contact.
Lamp or lamp housing (19% of reported cases) – The interior light assembly sits within or near the door frame. If the bulb, lens, or housing projects outward or is loose, it can obstruct the door's path or prevent the seal from sitting correctly.
PCB or door latch mechanism (5% of reported cases) – Electrical faults affecting the latch solenoid or the control board can prevent the latch from engaging, even if the door appears to close.
What you can try yourself (DIY)
If you're comfortable with basic inspection, start here:
1. Inspect the door seal Open the door fully and look around the rubber gasket. Check for visible tears, cracks, discolouration, or lumps of hardened rubber. Run your finger gently around the entire seal — it should feel smooth and pliable. If it's torn or distorted, replacement is usually straightforward and the seal is a wear part available for the WW90 range.
2. Check the lamp assembly Look inside the door frame and around the lamp housing (usually on the left side). Ensure the bulb and lens are not cracked or protruding. Gently press the housing to confirm it's seated firmly. If the lens is cracked or loose, this is a common culprit and the lamp assembly is replaceable.
3. Look for obstructions Run your eyes around the entire door opening. Check for debris, detergent residue, or damage to the frame itself that might prevent a tight seal.
4. Test the door action Close the door gently and listen for a click from the latch. If there's no click or the door feels springy, the mechanical latch or its electrical trigger may need attention.
If you find a torn seal or damaged lamp housing, many customers replace these parts themselves. If inspection finds no obvious damage, or if the door still won't close after checking these points, the latch mechanism or PCB is more likely to be at fault.
When to call an engineer
You'll need professional help if:
- The seal and lamp assembly look intact but the door still won't close or latch.
- The door latch makes no sound when you press it, or feels broken.
- You've replaced the seal and the problem persists.
- You're not confident opening the door panel to inspect the components.
Diagnosis of a faulty latch solenoid or PCB requires electrical testing and tools beyond typical DIY scope.
If you're in Northern Ireland, SMC Services can usually book a repair within 2-3 working days.