I just purchased a 2000 ezgo electric golf cart I plugged it in to charge all night. After using it a few minutes it appears to run out of charge. I've checked the water levels and the headlights are bright but when I plug the charger in it doesn't show any amps. How can I check to see if the charger is in fact working or if the batteries are already charged? Thanks and I appreciate any help as I know NOTHING about golf carts