Charger requires pressure to charge.
My charger needs pressure on the bottom near the 16 pin icon. It will not stay charging unless I sit there and physicly push it for hours.
iPhone 4S, iOS 7, ITUNES
What device are you describing as "charger"? The adapter that plugs into the mains has no "16 pin icon" that can react to pressure. I do not know of any 16 pin device that exists in tthe Apple world?