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Samsung WW90 5C Error Code – Drain Issue Diagnosis

SAMSUNG WW90 range · freestanding washing machine · based on 106 similar repairs

Diagnosed by Sean McCauley · SMC Services · Last verified 10 May 2026

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Likely causes (Samsung freestanding washing machine):

Problem summary

The 5C error code on Samsung WW90 models indicates a drain system fault. Your washing machine has detected that water is not draining properly from the drum or sump area. This error will usually stop the machine mid-cycle or prevent it from running until the fault is resolved.

Likely causes

Based on repair data from WW90 machines showing this error, the most common issues are:

Pump failure – The drain pump itself may have stopped working. This accounts for the majority of 5C errors seen in the field. The pump can fail due to age, motor burnout, or internal blockage.

Blocked drain path – Lint, coins, or debris may be obstructing the drain hose, filter, or internal pipes. This prevents water from flowing out even if the pump is working.

PCB (control board) fault – The circuit board that controls the pump may have failed, so it's not sending power to the pump even though the pump itself is intact.

Drain pump electrical connection – A loose, corroded, or damaged electrical connector between the board and pump can break the signal or power supply.

Why this needs an engineer

The drain system on a washing machine involves sealed pipes, a mechanical pump with an electric motor, and mains-voltage wiring. Identifying which component has failed requires specialist testing equipment and safe access to live electrical circuits.

Attempting to disassemble the pump assembly, replace the PCB, or test high-voltage connections without proper training risks electrical injury and may damage other components.

Our engineers carry the correct replacement pumps, looms, and PCBs for WW90 models and can test the system once any part is fitted to confirm the fault is resolved.

When to call SMC Services

Contact us if: - The 5C code appears when you try to run a cycle - You notice water pooling inside the machine or beneath it - The error returns after a power reset - The machine has been left standing unused for some time (seal or electrical degradation)

If you're in Northern Ireland, SMC Services can usually book a repair within 2–3 working days.

Step by step

  1. Warning sign: water inside the cabinet. If water is pooling inside the machine body or underneath it, stop using the machine immediately. This suggests a serious leak or pump failure that needs urgent professional attention.
  2. Warning sign: repeated error after reset. If you power-cycle the machine and the 5C code returns within a few minutes, the fault is persistent. This is not a temporary glitch and requires engineer diagnosis.
  3. Warning sign: burning smell or visible scorching. If you notice a burnt smell, visible scorch marks, or smoke, switch off the machine immediately and call an engineer. This may indicate an electrical short circuit.

Frequently asked questions

Can I just clear a blockage myself?
If you can safely access the external drain hose (usually at the back), you can disconnect it and check for obvious kinks or debris. However, internal blockages in the pump filter or tub drain require the machine to be partially dismantled. If you find no obvious external cause, the fault is likely electrical or mechanical, and an engineer is needed.
What if I reset the machine – will that clear the error?
A power reset (switching off at the wall for a few minutes) can occasionally clear a one-off sensor fault, but if the 5C code returns on the next cycle, a real fault exists. Do not ignore repeated errors.
Is the drain pump expensive to replace?
Pump costs vary depending on the exact part and whether the control board or electrical connections also need attention. An engineer's quote will give you a clear price once they've diagnosed the cause.
How long does a repair usually take?
Most drain-related repairs take 1–2 hours on site if the pump or connections are the issue. If the PCB needs replacement, the time may be slightly longer. The engineer will give an estimate once they've identified the fault.
Will my warranty cover this?
That depends on your machine's age, the terms of your original warranty, and whether you hold an extended plan. The engineer can advise once they've examined the machine, but we recommend checking your paperwork or manufacturer documentation first.

Get this fixed

The parts most often needed for this repair — order direct:

Fits your WW90 Samsung Drain Pump (DC31-00181A) £43.91 SMC02398 View part → Fits your WW90 Samsung Drain Pump (DC31-30008D) £47.65 SMC05796 View part → Fits your WW90 Samsung Main Pcb (DC92-01640G) £99.23 SMC05912 View part → Fits your WW90 Samsung Main Pcb (DC92-01768D) £86.82 SMC10912 View part →
Browse all spares

Prefer a pro? A local appliance engineer can carry out this repair. SMC's own repair service covers Northern Ireland only. The parts above ship UK-wide.

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About the data on this page

This page draws on 106 similar repairs from across 29 years of SMC Services records — over 116,000+ appliance repairs in total since 1997. The likely-cause percentages above are computed directly from the engineer reports we filed for this brand and fault, and we update them as new repairs come in.

SMC Services Ltd · Registered in Northern Ireland, Co. NI628091 · Domestic & Commercial Appliance Repairs.