My MacBook is a Battery Denier

Question

I have a four year old MacBook rev 1,1 (the original Intel Core Duo). Just recently it has begun denying the existence of its battery while still happily running unplugged. I get the X battery icon which claims "No Batteries Available". It is a fairly recent replacement battery and coconutBattery reported it was healthy and holding 90% of its original charge. The MagSafe adapter shows a green light. The battery lights are off, but when I press the button I get 3 of 5 lights.

It will run off the battery, it just won't recognize its existence nor charge it.

Previous to this, I would have to plug and unplug the MagSafe adapter a few times before it would charge the battery, but it would always recognize it.

coconutBattery will now crash with a divide by zero exception.

Things I have tried:

• My battery in another Macbook: it works and charges fine.
• A known good battery in my Macbook: denied.
• A known good power adapter: no effect.
• Resetting the SMC: no effect.
• Resetting the PRAM and NVRAM: no effect.
• Booting from a DVD: no effect.
• Replacing the Battery Connector: no effect.

Anything else I can try? Is there a part I can replace, or is this going to take a logic board replacement?

UPDATE: I pulled the computer apart and saw no black smoke nor Mynocks chewing on the power cables. However, it appears the laptop and the battery are putting their differences behind them. The laptop will now, from time to time, acknowledge the battery and charge it. The first time this happened, it was raining. The second time was next to a bathtub full of water. Extrapolating this curve, I will try throwing my laptop into the river to fix it.

UPDATE 2: I replaced the "Battery Connector w/Sleep Switch" because the laptop had developed narcolepsy. I had hoped this would cure its battery denial, but no dice.

Answer 1

Before you perform any hardware replacement, you might want to check the connection points on the laptop where the battery comes into electrical contact. Make sure everything is secure and clean.

There might be a part you can replace that goes between the motherboard and the battery connection point. Almost anything is cheaper than an older mac motherboard replacement. Assuming you are comfortable with this, have you taken the laptop apart and looked around to make sure anything isn't loose or melted/damaged? It sounds like it was something that was starting to fail and now is broken.

Answer 2

If you brought this to me for repair, these are the first things I would check from what you described in your initial post.

The battery connecter that is used on the MacBooks is very specific. Did you notice when you bought the replacement part if the pins were exactly the same configuration? If they are different that is why it may not have fixed your issue.

There is an Energy Star and a Non-Energy Star version of the battery connector.

Unlikely, but worth also checking/replacing is the DC-Inboard/Magsafe connector. This is the part that the connects the charger externally to the logic board internally.

If both of these are replaced with the proper parts, booting from a known good OS, testing with a known good battery and known good power adapter and it still does not work, then I would say it needs a new logic board. Based on the cost of that replacement and age of the machine it would not be worth repairing.