GE Microwave Error Code Humidity Sensor OPEN

This error means the microwave's control system has detected an open or defective circuit in the humidity sensor, which is the component that measures steam levels during cooking. Any defect in the sensor, its wiring, or the connector at CN8 on the power board will trigger this code. Sensor-based automatic cooking modes will not function correctly while this fault is active.

Basic microwave functions like timed cooking may still operate, but sensor-based cooking modes that rely on the humidity sensor will not work correctly and should not be trusted to determine doneness. The error does not indicate a fire or shock hazard in itself, but you should avoid relying on any automatic sensor cooking features until the fault is resolved.

If only the humidity sensor itself needs replacement, parts typically range from roughly $20 to $60 depending on the specific model. If the power board is the root cause, board replacements can range from $80 to $200 or more for parts alone. Adding professional labor, total repair costs generally fall between $100 and $300, though this varies by region and service provider.

A knowledgeable DIYer can attempt this repair by first disconnecting the sensor harness from CN8 on the power board and checking resistance values: Black-Red should read 6.5K ohms, Red-White should read 3.25K ohms, and Black-White should read 3.25K ohms. If readings are off, the sensor or harness needs replacement. Keep in mind that working inside a microwave involves high-voltage components, including the capacitor, which can retain a lethal charge even when unplugged. The capacitor must be safely discharged before any internal inspection.

Unplugging the microwave and restoring power may temporarily clear the error display, but the code will return as soon as the control board attempts to read the sensor again. A reset does not fix the underlying open circuit condition. The sensor, wiring, or connector must be inspected and repaired or replaced to permanently clear the fault.