Electrolux Dryer Error Code 0x31

Error code 0x31 on an Electrolux dryer indicates that the conductimetric (moisture) sensor is reporting a signal frequency that exceeds the expected operating range. The conductimetric sensor works by measuring the electrical conductivity of laundry as it tumbles past two sensor bars inside the drum. When the sensor detects moisture, it completes a low-level circuit and generates a frequency signal that the main control board interprets to determine how wet the load is. A frequency reading that is too high tells the control board that the signal is out of specification, which prevents the dryer from accurately managing the drying cycle.

The most common cause of this fault is a wiring issue between the humidity sensor and the main control board. Loose terminal connections, corroded connector pins, or a chafed wire that is shorting to another conductor can all distort the frequency signal and push it above the acceptable threshold. Because the sensor itself operates on a relatively simple circuit, wiring integrity is the first and most critical area to inspect before condemning any components.

If the wiring harness and all terminal connections check out as secure, clean, and undamaged, the fault likely originates at the main control board itself. A failed signal-processing circuit on the board can misread or generate an incorrect frequency value, triggering the 0x31 code even when the sensor and wiring are functioning correctly. In this scenario, the control board requires replacement to restore normal operation.