[RIP]

I've had zero experience with tests failures on this system. Apparently, few have. I'm just going by what I've read. Seems odd you would have that much going wrong all at once. The only common thread I see is the control panel. I'm sure several attempts at the calibration gives the same results. I would check the contacts on the panel connector for anything amiss. Have you tried disconnecting the battery to reset the HVAC module in the panel? If all looks good then I would suspect the module (computer). See if you can find a replacement panel in a junkyard. They are probably pricey elsewhere.