I won a BCG-34HD4 Battery Charger bought some years ago. It remained unused along with the batteries for very long. How to I check if the equipment is still in good order? The batteries are charging only slightly. Should I change the batteries or is some thing wrong with the charger? When I plug it a yellow light comes and in about 10 seconds starts blinking. Even after 12 hours of charging the blinking goes on. Do I have to dispose it off?