My Kenmore Electric Dryer (90 series) will hum when it is started, with the button but it will not turn on when the start button is released. I have already check the thermal fuse and it is good. I also check the switch next to this (not sure what it is called...4 terminals) and it is good. I was thinking it could be a motor relay, but I coudn't find one in the control panel. Any thoughts what it could be or what to check? Thanks.