LG Microwave Error Code E-33

E-33 indicates a weight sensor calibration error. During the sensor's initialization routine, the control board calculates a value called the K constant, and E-33 is triggered when that constant falls outside the allowed range of plus or minus 28 in hexadecimal. This prevents the microwave from using its automatic weight-based cooking functions until the sensor issue is corrected.

The E-33 error disables the automatic weight-based cooking modes, but basic microwave functions may still operate. However, using the appliance with an active fault code is not recommended, as the underlying sensor issue could indicate other problems with internal wiring or components. It is best to resolve the error before continued use.

Repair costs depend on whether the issue is a wiring problem or a failed sensor. If only a connector needs to be reseated, there may be no parts cost. If the weight sensor itself needs replacement, parts typically range from around 30 to 80 dollars depending on the model, with professional labor adding another 75 to 150 dollars or more. If the control board is at fault, repair costs can be significantly higher.

Some cases of E-33 can be addressed by a knowledgeable DIYer. Start by unplugging the microwave, inspecting the weight sensor for contamination or loose wiring, cleaning the sensor area, and reconnecting any loose harness connectors. If the error returns after these steps, the sensor likely needs to be replaced, which requires disassembling the microwave interior and working near high-voltage components. If you are not comfortable working inside a microwave, a qualified technician should handle the repair.

A reset by unplugging the microwave for a few minutes may temporarily clear the error code, but if the weight sensor or its wiring is faulty, the E-33 code will return the next time the sensor initialization routine runs. A reset alone is not a fix and should only be used as a first diagnostic step to confirm whether the fault is persistent.