Battery not detected, won't charge; strange connector on logic board?
I repair MacBooks as a hobby, and have worked on quite a few A1342 models. I'm working on one now that has me stumped by a couple of things.
Problem: The main problem with this computer is that the battery is not detected and therefore it does not charge.
Things I know:
- Charger will turn orange for approximately 3 seconds when you first power on, but then resets to green
- No water damage
- Computer displays "there are no available batteries" in top right of screen with [X] where the battery should be when booted into OSX
- I think I was able to get it to say "not charging" a few times (I think this was immediately following the slew of SMC resets), but I can't get it to repeat that now
Things I've tried:
- I have tried multiple, known-good batteries
- I have tried multiple, known-good chargers (both 60W and 85W varieties)
- I have tried multiple, known-good magsafe boards
- I have reset the PRAM (cmd,opt,p,r) and SMC (shift, ctrl, opt, pwr) multiple times
- I have tried the "power button down for 10 seconds" and the "power button down for 5 seconds, plug in charger, wait 5 seconds" methods, each to no avail
- I have re-installed OSX, both Snow Leopard and Lion
- I have tested the RAM and RAM slots, both are fine
Is there some fuse that controls battery recognition/charging that could be blown? Similar to the way the backlight fuse can blow, etc. If not, what should I check? There's no water damage and no other damage. I don't have a schematic for this board (820-2567-A) so I can't tell where the battery/charging circuit is.
Other things I noticed:
- This logic board, for some reason, has a connector on the board that I've never seen. I searched on eBay and Google for a picture of one like mine, but could not find any. It looks just like the bluetooth board connector (and is in fact located right next to it, near the fan) on the logic board, but it's twice as long (same width and pin layout and everything). What is this connector for? There's nothing to plug into it in the case, and I've never seen one before. It looks factory-done.
Edit: I can't get it to let me post a comment to your answer, so I'll just edit here.
I have tried everything you mentioned with no success. Something else I noticed tonight, though, which is very strange, is the fact that the laptop WILL run off of battery perfectly fine! I accidentally pulled the charger out while booted into OSX, and the laptop stayed on...so I left it unplugged. It ran fine for 10 minutes off of the battery, despite showing the "[X]" icon in the top right (it tells me there's no battery available, but I'm running off of it).
When I plug the charger in right now, running from battery and booted into OSX, it turns orange, but then to green, so not charging.
I'm baffled. The computer still is not charging, but now it shows the "[X]" although it runs from battery fine (the screen even dims when I remove the charger...so it obviously detects the change in voltage from charger to battery power.