Less than 7 year old. It started behaving oddly, with various lights coming on, running all night, etc. I tried pushing various buttons (including Cancel and the Normal/Heated Dry sequence twice) with door open and closed with various results but decided I need to be methodical in diagnosing the problem. I'm hoping that pushing button X with the door open and getting Y result means it is the control panel, but getting result Z means it is the control board, or something like that. IOW, hoping there is a diagnostic sequence that will reveal where the problem lies before just tearing it open and poking around with a multimeter. So starting over:

After powering off for 30 minutes then back on with door left open, Normal and Heated Dry are on, Dry and Start are blinking.

Are there certain steps I can take (door open, door closed, push certain buttons, etc.) to reveal where the issue lies? I do not want to start replacing $150 parts (control panel and control board) just to see what happens. Thank you.