Whirlpool Gold Quiet Partner III Reset Control Panel but still won't start

I have read all the threads and did all the troubleshooting. Reset the Control Panel by pressing Sani-heated dry-Sani and it resets all the lights. The Cancel Start button works. The problem isn’t the lock either. I set all the controls and push the start button and nothing all it shows is 2 lines, they don’t blink make no noise nothing. I put hot water in it and push the Cancel Start button and it drains that’s it. I set the delay start and after a few seconds it goes out. HELP Do I need to replace the start button, the latch, clean the connections, what. I am a technician but haven’t worked in years and am too tired too take it apart to troubleshoot. I can replace any part if I know what I need to replace. I am stumped. Thank you for any help. Oh yeah I bought this used and was told it worked.