Hi, I tested this units damper it works fine. I tested 12v output to temperature control board its fine. What happens is the unit will display door open when its closed, it will also keep temperature displayed when it is open but both of these are intermittent. I tested door switch it is fine. When door switch is closed fan comes on and lights turn off every time but display shows door open or temp. It also opens and closes damper too. My question how to determine if it is a bad data signal from main board or temperature control board is getting signal but is bad?
One other thing, during malfunctioning display while testing, I heard a humming noise coming from display board area. Thanks I hope someone can help me asap. I already have service manual.
PS- freezer temp is fine damper is closed to ff side.