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Hello, I hate to be too brief, but those symptoms point almost exclusively to bad printed circuit card.
We can do a heat stress on it
Use a hair drier to slowly warm the printed circuit card up to120F or a bit warmer, but not over 140F... if there is any change in the error codes or other furnace behavior... the card has a cracked micro circuit that opens and closes as the card expands and contracts... that proves a bad printed circuit card.
No change however does not prove the card is good however... but a change proves the card is definitely bad.
Let me know what you can discover. we can go from there.