The circumstances of my Macbook Air (late 2010 model) and its inability to charge the battery are a bit unique from the other cases I've read about on forums:
- My battery would not charge, and the computer would die instantly upon removing the MagSafe cable.
- The MagSafe indicator light would sometimes show a very faint green, but most of the time, it was completely off.
- I tried resetting the SMC; nothing changed.
- I tried multiple outlets; nothing changed.
Coconut Battery gave a "check battery" status, indicating it needed to be replaced. I did so.
Coconut Battery likes the new battery, but it has the same issues:
- When the computer is on and plugged in, the system's power status says "Not charging."
- When I unplug, the battery powers the system just fine. But eventually, it will lose power from not charging, and I'll be back at Square One.
- The MagSafe indicator light is still off with the new battery. I've tried jiggling it when it is in the port; no change.
- I've tried cleaning out the MagSafe port; no change.
- I've tried using a different duckhead adapter; no change.
- The pins on the MagSafe plug appear fine.
- I've tried resetting the SMC several more times; no change.
I'm out of ideas. I suppose I could try using a different power adapter, but I don't have another on-hand with a compatible MagSafe adapter. Apple's next recommended step is to get the machine serviced. But I'd rather pursue more DIY options if they exist.
Best Answer
Once you've reset the SMC once - that's out of the picture. Let's assume your situation is different than all the rest - My MacBook Air won't charge - and it's not the adapter or the pins or something you can fix and identify without turning a screw or opening the Mac.
Now you have to figure if the adapter is bad - you didn't explicitly say that, but it's probably not since you would report that the system is dead and won't power on ever again if you can't get some adapter to put charge back in the battery when the machine is off and sitting overnight.
At this point, you still need a hardware repair.
A repair shop might be able to tell if the battery needs replacing but since you did that - you either have a totally unlikely circumstance that the old battery failed in a non-common way and the new battery happens to have the same non-common failure mode. The new battery should show clean in system information even if it won't charge due to other issues. The real key is if the new battery shows "check battery" status you would want to return that part if you're sure you didn't do the repair wrong (you'll risk being charged for the shipping and not get your money back if the part is good) but it's far more likely the fault is with the charging circuitry and power handling circuitry. Also, you probably needed a new battery too so that's out of the way now.
The likely cause is you need a new MagSafe power in board for the Air or a new logic board. Sorry to deliver the news, but the alternative to this diagnosis is that the cables or the new battery were bad and it will be costly to figure that out as well.