LG Washer Error Code C4

The C4 code on an LG washer signals a water supply or temperature fault. It appears when the hot and cold supply hoses are connected to the wrong inlets, when water temperature exceeds 60 degrees Celsius during a dry cycle via the dry valve, or when temperature exceeds 60 degrees Celsius during Wool or Lingerie wash courses. The washer stops operation to prevent damage to fabrics or internal components.

No, you should not continue using the washer while C4 is active. The machine has halted because it detected an unsafe or out-of-range temperature condition. Running the washer under these conditions could damage delicate fabrics or stress internal components. Diagnose and resolve the cause before resuming use.

If the fix is simply reconnecting reversed supply hoses, there is no parts cost and only your time is involved. If the issue requires replacing a temperature sensor or inlet valve, parts typically range from $15 to $80 depending on the component, with professional labor adding $80 to $150 or more depending on your location and the technician. Diagnosing the exact faulty component before ordering parts will help avoid unnecessary expense.

Start by turning off the water supply and checking that the cold hose is connected to the cold inlet and the warm hose is connected to the warm inlet on the back of the washer. If the hoses are correct, check your home's water heater thermostat to ensure the supply temperature is not above 60 degrees Celsius. If the error persists after correcting connections and supply temperature, a temperature sensor or inlet valve may need to be inspected and replaced.

A reset may temporarily clear the C4 display, but the code will return if the underlying problem is not corrected. If the hoses are reversed or the water supply temperature is too high, those issues must be physically resolved first. A reset alone is not a fix and should only be used after addressing the root cause.