LG Washer Error Code 18C1

The 18C1 code on an LG washer indicates a MEMS PB temperature sensor error in the upper washer compartment. The machine has detected that it cannot receive a valid temperature reading from the upper drum's sensor circuit. This causes the washer to stop operating as a protective measure until the fault is resolved.

It is not recommended to continue running the washer while this fault is active. The machine uses temperature sensor feedback to regulate the wash cycle safely, and operating without a reliable reading could result in improper water temperatures or damage to internal components. The washer will typically halt operation on its own when this code appears.

Repair costs vary depending on the root cause. If only the wire connections need to be reseated or cleaned, costs may be limited to a service call fee, typically in the range of $75 to $150. If the temperature sensor requires replacement, parts and labor combined could range from $150 to $300. A main control board replacement is the most expensive scenario, often ranging from $250 to $500 or more depending on parts availability and labor rates in your area.

Some causes of this error are DIY-friendly. You can inspect the wire connections to the temperature sensor yourself, looking for loose, unplugged, or visibly damaged connectors. If the wiring appears intact, testing the sensor itself requires a multimeter and some familiarity with reading resistance values. Replacing a sensor or control board is more involved and may be better suited to a qualified technician.

A reset may temporarily clear the error code display, but the fault will return if the underlying problem has not been fixed. To clear the code permanently, the faulty wiring connection or defective temperature sensor must be repaired or replaced. Repeated resets without addressing the root cause will not resolve the issue.