Whirlpool WSF7256 IX - Board self test

Board self test
Troubleshooting
The User Interface Board turns ON all LEDs for 3 seconds after each plug-in.
This allow a visual verification that all the LEDs are properly working.
The User Interface board itself can not recognize any failure at this stage.
During this time no operations will be allowed. (e.g. button pressure, function engagements)