DWwill not start?

Kenmore Dishwasher Model # 665.13732K600 Symptoms: When you depress Smart Wash (or Normal or Pots/Pans) sometimes it blinks, but will not start when Start depressed. I can hit cancel, then Smart Wash again, and Smart Wash lights up, along with Heated Dry, but again will not start when Start button depressed I replaced the Electronic Control board and it worked fine for about 6 weeks. Then repeated same pattern of blinking and not running. I again replaced the Electronic Control board a second time, it worked fine another month or so, and is now back to not working again. I found on line a process to reset the control panel by turning power off, disconnecting the 15 pin ribbon that goes to buttons, turning the power on, closing the door, let it cycle about 2 minutes turn power off, reconnect ribbon, turn power on and dishwasher worked properly. The next attempt to start dishwasher fails. After doing that several times and it working, now it does not work at all. Even after rebooting.