I have always been able to short T and H to get the harvest cycle to start. That's not working now. I am, however, able to get the motor to run (N and M) and the water valve (L and V), and also the mold heater.

The sensor bar is in the down position, and the two test holes (I forget which two now, but I know I had the correct two when I checked earlier) to check its resistance have ~0 ohms, which tells me the bar is properly down.

So why wouldn't shorting T and H do anything if everything else seems to be in place?