I would NOT be surprised if that board is the problem.
This problem, 3 cab blinks and chuff stopping, started shortly after the engine was brand new, but a RESET normally worked for awhile. It seemed to work for awhile until the engine got warm, and then the 3 blinks would start and loss of chuff.
Now after the reset, after replacing the fan motor, there are NO more cab light blinks, but the chuff & smoke will NOT come back.
Can that board be bench tested w/o the engine?