GE DRYER DBS453EBOWW won't stay on?

The dryer has operated great with no problems for 7 years. Now when you turn the START switch it will come on but once you let it go it goes off. Tried holding the button to see if other functions work. Still heats and tumbles nicely. But it just won't stay on. Can't hold button for entire loads. (And is that dangerous, say for example, you want to dry one thing in an emergency?)