Hi,
Here's our main thread on this issue:
Hi there, For almost a year now my dishwasher would periodically beep like when the door was being opened. It was annoying, but it still worked. A few months ago it would sometimes be unresponsive to button presses, but cycling the circuit breaker would bring it back to life. This afternoon the...
www.applianceblog.com
This thread is how I helped another member fix his:
My dishwasher is less than 3 years old. A few months ago, the display would randomly light up and beep. The dishwasher worked as it should other than that. We came back from vacation in May and it wouldn't work at all. A "technician" came out and said it was the main board but cold also be the...
www.applianceblog.com
If the door wire harness is good. Then its the UI Board that is the culprit, since the machine control board(underneath the dishwasher) is blinking.
Here's the user interface(UI) Board for your model:
WD21X31910
Remember--->You have to set the personality jumpers on the new UI Board before you install it or it will not work, the instructions that came with the new UI Board show you how to do it.
This video gives you the general idea of how to replace it:
Jake