This model does NOT have the small access cover in front. Washer machine stopped with an nD code (Not Draining). I am mechanically inclined. I took off the back access cover. Manually drained system (Water flowed out very fast). Took hoses apart and checked for plugging. Check valve is fine. Put 120 VAC to drain motor works fine. Put a volt meter to the power supply for the drain motor. Then put system in quick test mode and manually activated the drain pump (Select “soil” button). Volt meter blinked for ½ second at maybe 1 volt and then back to zero volts. Changed out main control board (DC41-00066A both front and back boards). Same problem. What am I missing?