Our washer was working intermittently. Sometimes we had to unplug it and then reset it before it would go to the next stage in the washing cycle.

Changed the actuator but that did nothing.
Pulled the pump and checked for debris - nothing.
Blew through the hose to the pressure switch but no blockage.
Tried the diagnostic mode (no screen) and it would only start in the Heavy Duty and Hand wash cycles.

Removed the back cover and checked all the connections but no difference.
Finally, I purchased a replacement Control Panel (not user interface) and installed it. Followed the instructions for re-calibration and that fixed it.

Washer now starts in any cycle and runs perfectly. Cost about $100 and 15 minutes of my time.