A Whirlpool dishwasher that does not stop running presents a myriad of problems. If the water level exceeds the appliance's capacity, it will overflow and cause water damage to the surrounding areas. In addition, abnormal use of the dishwasher will prematurely wear out its components. A faulty timer motor or heating element may be causing the dishwasher's to continue running past its expected cycles and times. A defective thermostat or fill valve may also prevent the machine from shutting off. In addition, a malfunctioning control board may be the culprit.
A defective timer motor may be causing the dishwasher to keep running. The timer motor determines how long each module and cycle of the appliance lasts. When the timer motor malfunctions, the dishwasher performs erratically, and it may not stop or start cycles correctly, or it may force the machine to continue operating repetitively.
An issue with the healing element can result in the dishwasher operating continuously. The heating element performs one or two functions depending on the dishwasher model: it heats the water or dries the dishes, or both. If the heating element fails to function properly, the dishwasher's cycles will not fully complete and the machine will remain engaged.
The dishwasher will continue to run if the thermostat malfunctions. The thermostat controls the timer motor circuit and will not allow it to progress to the next cycle until the water reaches the desired temperature. If the thermostat is defective, it will not acknowledge that the proper temperature has been achieved or allow the next cycle to initiate, and instead will keep the dishwasher locked in the wash cycle.
An issue with the fill valve will also cause the dishwasher to continue running. The hoses for hot and cold water are connected to the appliance at the fill valve. If the valve is mechanically stuck open, water will keep flowing into the machine even if the dishwasher is unplugged.
A malfunctioning control board can prevent the dishwasher from shutting off. The control board regulates all of the dishwasher's functions. However, if there is a glitch in the control board, the dishwasher will respond erratically -- or not at all -- when the start, stop and other buttons are pressed and may cause the dishwasher to get hung in one cycle.