Chosen Solution
I recently installed a new (aftermarket) battery in my MacBook Air 11" after the original battery stopped working. After replacing the battery status reads Replace Now. Not charging. After some research I decided to replace the i/o board but unfortunately I get the same result. Suggestions? Should I assume the new battery is faulty? Or should I try replacing the i/o board cable as well? Update (09/30/2015) In addition: I have tried two different MagSafe chargers and also reset the SMC twice.
Try a PRAM reset holding alt, cmd and R+P on start up until your hear the chime again. This should enable the macbook to attempt to charge, failing that clean the charger ports well with alcohol using a paintbrush/toothbrush - then try again. This has worked for me in the past. Alternatively you may have a faulty battery - aftermarket ones can occassionally arrive without charge.
