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Hello, tell me if the blower motor is warm or hot to the touch or not, if it is hot or warm the motor's run capacitor ($7) is most likely bad... testing can be complex its easiest to replace it.
Next feel for up and down play in the blower motor motor shaft if you can detect any play at all, the bearings are bad and the motor needs to be replaced.
LIfe span of those motors is in the 7 to 10 year range, if the motor is older than that, its due to fail
Look all that over, if you miss me tonight, I will pick up your response first thing in the morning, We can go from there.
Hello again electronic feed backs in AC printed circuit cards can give ghost reads that can be misleading
the fan will have heat and cool leads running to the motor the only valid red you will ever get is between COMMON and the cool lead with the thermostat fan switch on, and common and heat lead with the thermostat calling for heating (after a 20 to 30 second delay).
One of the better tests we can do on the printed circuit board is a heat stress test 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 how that test turns out, If you miss me tonight I will pick up your response first thing in the morning. I am off to bed in 30 minutes or so,