LG Microwave Error Code E-28

E-28 on an LG microwave indicates a sensor short error. The humidity sensor used during automatic sensor cooking modes has been detected with a slight short across its terminals. The microwave triggers this code to prevent inaccurate cooking cycles and flag the fault for diagnosis.

It is not recommended to continue using the microwave while E-28 is active. The sensor fault can cause sensor cooking modes to behave unpredictably, and the underlying short condition should be diagnosed before resuming use. Discontinuing use until the fault is resolved is the safer approach.

Repair costs vary depending on the root cause. A replacement humidity sensor typically ranges from around $20 to $60 for the part, while professional labor can add $80 to $150 or more depending on the service provider. If the control board is involved, costs will be higher, potentially making repair less economical on older units.

Some causes, such as condensation on the sensor or a dirty connector, can be addressed with careful inspection and cleaning. However, if the sensor itself has failed or the wiring harness is damaged, replacement parts will be needed. Microwave repair involves high-voltage components, so technicians recommend disconnecting power and exercising caution before opening the unit.

A power reset by unplugging the unit for a minute may temporarily clear the display, but the error will return if the sensor short condition still exists. The root cause, whether a faulty sensor, damaged wiring, or moisture intrusion, must be corrected for the error to be permanently resolved.