Maytag Dryer Error Code D18

The D18 error code on a Maytag dryer indicates an Axial Probe Fault. This fault is triggered when the axial thermistor reads a temperature value that falls outside its expected operating range for a continuous period of more than 30 seconds. The axial thermistor is a temperature-sensing component positioned to monitor airflow temperature at a specific point in the dryer's drum or exhaust pathway. Like most thermistors, it operates by changing electrical resistance in response to temperature. When the control board detects a resistance value that corresponds to an out-of-range temperature reading, it flags the D18 fault and interrupts normal operation.

The two most common root causes of this fault are an open circuit or a shorted condition within the thermistor or its wiring harness. An open thermistor occurs when the sensor's internal element breaks, causing resistance to spike dramatically or drop to zero. A shorted thermistor forces resistance to collapse, producing a reading that the control interprets as an extreme temperature. Both conditions prevent the control board from accurately monitoring drum temperature, which is critical for safe and efficient drying cycles.

One important characteristic of the D18 fault is that it supports automatic clearing. If the condition that triggered the fault resolves on its own, such as a loose connector reseating or a temporary sensor fluctuation correcting itself, the control board will automatically return to READY Mode without requiring a manual reset. However, if the fault reappears consistently, a physical inspection of the axial thermistor, its connector, and the associated wiring harness is necessary to identify and correct the underlying problem.