What this error means
Water supply fault — the dishwasher is not filling with water correctly
The 4C or 4E error means the dishwasher has failed to detect sufficient water entering during the fill phase. This is most commonly caused by a closed or partially open water supply tap, a kinked inlet hose, a blocked inlet filter mesh, or low water pressure. A faulty solenoid inlet valve can also produce this fault.
What you'll need first
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Step-by-step
Symptoms to look for
- Dishwasher starts but does not fill with water
- Programme stops within the first few minutes with 4C or 4E displayed
- Fill phase takes far longer than normal before faulting
- Machine makes a humming sound but no water is heard entering
How to fix it
Find the cold water isolation tap under the sink. Turn it fully anti-clockwise. If uncertain whether it moved, close fully clockwise then reopen anti-clockwise.
Open the under-sink cabinet and trace the hose from the tap fitting to the back of the dishwasher. Straighten every kink and sharp bend. Ease the dishwasher forward slightly if the hose is pinched between the machine and the cabinet.
Turn the tap off. Place a towel under the hose connection at the back of the machine. Unscrew the hose fitting anti-clockwise. Inside the machine's inlet port is a small flat or cylindrical mesh filter. Remove it with tweezers, rinse under running water and scrub with a toothbrush to clear limescale and debris. Refit firmly.
With the hose disconnected from the machine, point it into a bucket and open the tap briefly for 3 seconds. You should see a strong, uninterrupted flow. A weak trickle indicates a supply pressure problem at the property — Samsung dishwashers require a minimum of 0.5 bar to fill correctly.
With the dishwasher completely unplugged, remove the lower kickplate panel. The inlet valve is where the hose connects internally — a solenoid body with an electrical connector. Check for corrosion or mineral deposits.
Reassemble everything, restore water supply and power, and run a Quick Wash. The dishwasher should begin filling within 60 seconds.
When to call an engineer
- Water supply pressure confirmed adequate but 4C persists after filter cleaning
- Inlet valve solenoid reads open circuit on a multimeter — valve has failed
- Aqua Stop hose outer sleeve is damp or bulging — hose must be replaced
- Wiring to inlet valve is burnt, corroded, or connector is melted
Frequently asked questions
Why does 4C appear even though the water is connected?
What minimum water pressure does a Samsung dishwasher need?
What is an Aqua Stop hose?
Is it safe to use the dishwasher after 4C?
🎯 What is likely causing this fault?
⚠️ Estimates based on common faults — not a guaranteed diagnosis. Always verify before ordering parts.
Parts you may need
Enter your model number to filter results to your exact machine
Usually found on a label inside the door frame or on the back panel of the machine.
| Part | Approx. UK Cost | Find it |
|---|---|---|
| Water Inlet Valve | £15 - £20 | 🛒 Amazon UK → |
| Water Inlet Valve | £15 - £20 | 🏷️ eBay UK → |
| Aquastop Hose | £20 - £30 | 🛒 Amazon UK → |
| Aquastop Hose | £20 - £30 | 🏷️ 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.