The 4C error means water supply issue — dishwasher didn't fill within expected time.
The Samsung dishwasher displays the 4C error and halts the current cycle until the underlying problem is fixed.
Check these in order. The first cause accounts for the majority of 4C errors.
The shutoff valve under the kitchen sink that feeds the dishwasher is partially or fully closed. This is the first thing to check — it's a 5-second fix if this is the cause.
The supply hose connecting the valve to the dishwasher (usually runs under the cabinet floor) can get kinked, especially after the dishwasher has been pushed back or reinstalled.
A mesh screen at the inlet valve inlet port traps sediment. Over time this screen can become partially blocked, reducing flow below the fill threshold.
If supply, hose, and screen are all clear, the inlet valve solenoid itself may have failed. Test with a multimeter and replace if no continuity when energized.
Follow these in order. Stop as soon as the error clears.
Open the cabinet under the sink and turn the supply valve fully counterclockwise. This is the most common fix.
Cut power before inspecting components.
Trace the supply hose from the valve to the dishwasher. Straighten any kinks.
Disconnect the supply hose at the back of the unit. Remove the small mesh screen from the inlet port and rinse under running water. Reinstall and reconnect hose.
Run a short wash cycle. Listen for water entering the dishwasher within the first minute.
If water supply is verified good but 4C persists, test the inlet valve solenoid with a multimeter and replace if faulty.
For warranty service, contact Samsung support ↗ or a certified appliance technician.