Electrolux dryers use an electronic keypad to control the dryer temperature, cycle and drying mode. If the keypad or the control panel behind it breaks down, the machine displays a "key stuck" error. Key stuck errors ultimately require the help of a technician, as the electronics probably have to be replaced. Before calling your technician, troubleshoot the machine yourself.
Control Board Failure
If you get a key stuck message, it usually means your control board isn't working properly. Check whether any of the buttons on your control panel are pressed down when they shouldn't be. If any button is, try pressing it again to release it. If you can't release the buttons this way, you probably need your service technician to look at the machine and possibly replace the control board.
Before calling for service, try resetting your machine. Sometimes the electronic equipment freezes and resetting the machine can clear the error code. To reset your Electrolux dryer, press and hold the "temperature" and "dryness" buttons simultaneously. Keep these buttons depressed for at least six seconds to reset the machine. If this doesn't clear your error code, you likely need service.
Turning Machine Off
In addition to resetting the machine, you can sometimes clear error codes by turning the power off, then on again. Unplug the machine, wait about 30 seconds and plug it back in. If the error code doesn't come back up, unplugging the machine successfully reset it. If the error code persists, you need to call for service.
A key stuck error indicates a problem with the electronics. The problem is most likely in the control board, although it can also be in the keypad interface. You can check if your lights and buttons work yourself by going into diagnostic mode. Press "cancel" followed by any button. Turn the selector to the far left and simultaneously press down "cancel" and the leftmost button under the display. After three seconds, all the lights will flash. Turn the selector knob until "Lights/button test" comes up in the display and press each button to see if it works. Pass this information onto your technician when he comes to service the machine.