In my case my macbook would not charge too and the light wouldn't come on. When I connect my charger my battery percentage basically stays at the same percentage. I read somewhere that the problem may be that the charger gets too cold for it to work. That made sense in my case because I charged my macbook next to a big window with a bit of cold air coming in (this is during winter time). What I tried is (and this may sound ridiculous) blow dry the block part and the connector part (for a minute or 2 be a bit careful though) and after doing that the light quickly turned green and charged my macbook. I don't think blowdrying the charger is a very good thing but I just wanted to quickly test if the charger being too cold was the problem. I have read on others sites that people tried other methods to heat it up like sitting on it (for 5 minutes) or putting it under their armpit. I must say my charger turned on for just a couple of seconds but that atleast proved to me that the charger being too cold was the problem. It probably just turned on for acouple of seconds because I used my macbook in a room where it's pretty cold for a long time. In other words, it's still too cold for it to work consistently. I think the charger just needs to be in a warm enough area for awhile. Another reason why I think the mac charger being too cold is the problem is because when I use my macbook in another room where it's pretty warm the charger out of nowhere starts working after acouple of hours.