How To Fix A Dryer That Won't Shut Off

The door switch is a safety feature found in all dryers. It is an on and off type switch that prevents the dryer drum from turning when the door is opened. If the dryer continues to tumble after the door is open the problem is most likely the door switch. In most brands of dryers, the switch is located behind the front panel with the switch button protruding into the door opening. The switch and can be tested with a multi-tester for continuity and it may have two or more terminals. The test should be made between the terminals marked “C” and “NO” and should read infinite ohms when the door is open or when the button is not depressed. This test should only be made with when the dryer is unplugged.

Located in the control console of the dryer the timer consists of a small motor connected to a series of gears that rotate cams, which turn electric contacts off and on inside the timer. The timer contacts control the dryer motor as well as the heat circuit and the timer motor itself. A defective timer motor or a defect in the timer’s electrical contacts can cause the timer motor to fail and the timer will need to be replaced. The contacts can be checked for continuity with a multi-meter. This test should only be made when the dryer is unplugged.

On gas and electric dryers that have an “Auto Dry” cycle, the cycling thermostat is often used to advance the timer as well regulate the drum temperature. Essentially, thermostat will alternately turn on the heat source or the timer motor when the temperature has been satisfied. To check this thermostat, you will have to check for power to the timer motor with a multi-meter, during a cycle. This is a live voltage test and caution should be used.

Some dryers will use a cool down thermostat to tumble the clothes without heat, at the end of the dry cycle. Power is routed through this thermostat to the drive motor to keep it running until the drum temperature has dropped to a specific temperature. If this thermostat fails it can cause the drum to turn indefinitely or until the door is opened. You can check the thermostat for continuity with a multi-meter. This test should only be made with the power removed from the dryer.