4C (also shown as 4E on older Samsung machines) is a water supply error. The washer started a cycle, called for water, and did not sense enough arriving within the time it allows. Nine times out of ten the cause is outside the machine — a closed tap, a kinked hose or a clogged inlet filter screen — not a failed part.
What the 4C code means
During fill, a Samsung washer monitors the water level with a pressure sensor. It opens the inlet valve, waits, and expects the level to rise at a predictable rate. If the level does not reach the target within roughly the time the control board allows, it stops filling and displays 4C rather than running the motor against an empty or half-filled drum.
This is a protective response, not a failure report. The machine is telling you it did not get the water it asked for — it is not telling you which part is at fault.
Common causes
| Cause | How likely | What you would notice |
|---|---|---|
| Tap turned off or partly open | Very common | No water sound at all when the cycle starts |
| Kinked or crushed inlet hose | Very common | Hose pinched behind the machine or against the wall |
| Blocked inlet filter screen | Common | Fill is very slow; worse on the hot or cold side only |
| Frozen inlet hose | Seasonal | Cold weather, machine in a garage, outbuilding or unheated utility |
| Low household water pressure | Occasional | Other taps in the house are also weak |
| Failed water inlet valve | Less common | Tap is on, filters are clear, still no fill |
| Pressure sensor or wiring fault | Uncommon | Drum fills normally but the code still appears |
How to fix it
Switch the washer off at the wall and close both water taps. You will be disconnecting hoses, so have a towel and a shallow tray ready — there is always water left in the line.
- Check both taps are fully open
Sounds obvious, and it is still the single most common cause. Open each tap fully. If the machine only takes cold water, check that one. A tap that was closed for a holiday or a previous repair is often the whole story.
- Straighten the inlet hoses
Pull the machine forward and look at the hoses along their whole length. A washer pushed back against a wall will crush a hose against the connector. Any kink, twist or sharp bend restricts flow enough to trigger the code.
- Clean the inlet filter screens
Unscrew the hose from the back of the machine. Inside the inlet port there is a small mesh filter. Pick it out carefully with pliers or a small screwdriver, rinse it under a tap to clear grit and scale, and refit it. Do the same at the tap end of the hose. This is the fix in a large share of cases, particularly in hard-water areas.
- Test the water pressure
Put the hose end into a bucket, open the tap, and check that you get a strong, steady flow. A weak trickle means the problem is in the plumbing, not the washer. Samsung machines generally expect somewhere around 20–116 psi; well below that and the fill will time out.
- Rule out a frozen hose
If the machine is in an unheated space and the weather has been below freezing, the hose or the tap may be iced up. Warm it gently with towels soaked in hot water. Never use a heat gun, blowtorch or boiling water on a plastic hose or valve body.
- Reset and retest
Unplug the washer for about a minute, plug it back in, and run a short rinse-and-spin. Watch and listen during the first minute: you should hear the valve click and water enter. If it fills normally, the fault is cleared.
4C, 4C2 and 4E — what is the difference?
These codes look similar and mean different things, so it is worth being precise:
- 4C — general water supply error, the one covered above.
- 4C2 — hot and cold inlets connected the wrong way round, or hot water fed to a cold-fill-only machine. Common straight after an installation or a house move.
- 4E — the same water supply fault as 4C, shown on older Samsung model ranges.
If your machine has just been installed or moved and shows 4C2, swap the hose connections before assuming anything has failed.
When to call a professional
If the taps are open, the hoses are clear, the filters are clean and pressure at the hose end is strong, but the drum still will not fill, the likely culprits are the water inlet valve, the pressure sensor or the control board. Replacing an inlet valve means working inside the cabinet next to mains wiring and live components.
Stop and call a qualified appliance technician or electrician if you find scorched or melted wiring, smell burning, see water that has reached electrical components, or if the fault returns immediately after a repair. Never bypass a safety device — thermal fuses, door interlocks and flood switches fail for a reason, and defeating one converts a broken appliance into a fire or flood risk.
