Contact cleaner and compressed air is what I use, unless corrosion is found. Then I shine pins up with a tiny chunk of scotchbrite pad glued to a stick. Corroded sockets are cleaned with baking soda & warm water then flushed with contact cleaner and air. As Mac said... takes a lot of patience.
Don't use lithium grease in the connectors, it absorbs water and degrades the seal packs. Dielectric grease only.
Don't use lithium grease in the connectors, it absorbs water and degrades the seal packs. Dielectric grease only.