Hello,
I have a Carrier 58DLA090-10116 Furnace and I am not getting any readout on my digital thermostat controller inside the house with no voltage. Went and pulled the dust cover off the control board inside the furnace (Carrier HK42FZ014 Control Board) and checked the fuse and connection and all were fine. Put cover back on and thermostat was working again with the AC performing fine. A couple of hours later I went to change the thermostat and once I hit the temp down button, unit went blank again. Went back out and checked the connections on the control board and all seemed tight. Pulled the fuse and it still looked good, however unit still dead at the thermostat.

Is this a bad control board issue? If not best guess?

Thanks