The GE gas dryer wouldn't start. Used on line tools to find the most likely causes; door switch, start switch failure, over temp fuse, belt failure or one of the thermostats - no joy. You need a volt meter and you should go here first although someone familiar with the dryer might tell you that the timer control turns with out resistance.
Turned out that the Timer Control knob was cracked and was not turning the timer control. The control had timed out in the off condition and of course wouldn't start. Finally noticed it when the knob fell off when I was trouble shooting behind the control panel. The hub has a metal clip inside the hub and a D shaped hole but the hub was cracked. Ordered a new knob and epoxied the old knob for a temporary solution. The knob is molded with hollows for the control wing. Fill with 30 min.epoxy and use a bull dog clamp to hold the split together. Second step mix up some more epoxy and apply it to the end of the hub and wrap it with some common thread, coating it with epoxy every couple of wraps. Worked well until the new knob arrived.