Question: If the gold plating on the surface of via holes is not removed from the printed circuit boards, does this constitute a defect or failure of the board’s acceptance in final assembly?
Answer: The gold plating on boards is typically an ENIG coating, which is Electroless Nickell, Immersion Gold plating. There is no requirement to remove this gold plating prior to soldering. The only requirement for the removal of gold is for component leads and terminals which will be soldered to the printed circuit board itself. So if there is gold on the vias, it is not a defect.