LEDs on dryer display knob will not light up. Coincidentally the dryer will not turn "on" either.

• Breaker is not tripped.
  
• Light inside drum IS working
  

I replaced circuit board and that did not remedy the problem. i can't use the on-board diagnostics because the LEDs won't turn on. The dryer had been working normally up until now.

Thanks in advance for any help/advise that you have. :)