I need a hint of how to determine which board to replace, the control or the main board. I am getting no DC power to the dispenser motor. The door flap opens, lights on the door come on, just no power to the auger motor. The motor works on the bench.

I have tested all the “door closed” switches and the “ice bin in place” switch. All good. I removed the motor and confirmed on the bench that is works properly. I also confirmed no power is reaching the motor through the harness. I also confirmed the continuity of the harness between the main board and the motor.

So, what is left is a problem with the control board in the door or a problem with the main board near the compressor.

It appears there is serial communication taking place between the control board and the main board, which will be difficult to test without a test device I do not own.

Thanks for any hints!