MacBook battery firmware fix reveals flaws, recall recollected

The battery firmware patch Apple last week provided for users of 15-inch MacBook and MacBook Pro notebooks may have uncovered a batch of problem batteries. The company said the problem batteries don't pose a safety risk, however, users should request a replacement.

Now, if you're still having trouble charging your battery or symptoms such as your MacBook or MacBook Pro not waking from sleep (or even turning on altogether), or not recognizing the AC adapter, you might want to try resetting the System Management Controller.

The SMC is an ASIC that controls a wide range of hardware, such as waking and sleeping, screen's backlight, when your hard disk spins down and I/O when the computer is sleeping. Some sites suggest performing this reset if you have trouble after applying the Battery Update 1.3.

When the settings get corrupted, things can go haywire. Apple says that you should restart the computer first to see if that resolves the problem before resetting the SMC.

Here are the steps, found on the SMC Apple Support document:

1. If the computer is on, turn it off. 2. Disconnect the AC Adapter and remove the computer's battery. 3. Press and hold down the power button for 5 seconds and then release the button. 4. Reconnect the battery and AC Adapter. 5. Press the Power button to restart the computer.

Update: When I wrote this up this morning, I'm sorry to say that I conflated the latest 1.3 flavor of Battery Update with the previous Battery Update 1.2, which was released last April. And Apple called me about this. However, some users may have discovered the previous problem now and I've asked Apple if the recall from spring still holds.

According to to the previous Battery Update 1.2 Apple Support document, the patch should be applied to all MacBook and MacBook Pros as well as extra batteries bought between February 2006 (when the MacBook Pro shipped) and April 2007.

Apple called the problem a "performance issue," a support-speak way of saying that the battery can stop working abruptly after a short period of time, even when the system monitor reports that the battery has plenty of juice and hours to go before losing power.

(Such is the case now with my MacBook Pro and its battery, both of which were purchased in 2006 during the time frame mentioned. My battery says it has 89 percent capacity when it goes dead after only 16 minutes working on battery power. The readout says that it should go for hours. I'm waiting on Apple now to see if I'm still covered under the older recall.)

Apple provided a list of symptoms for batteries with "issues:"

Affected batteries will have one or more of the following symptoms: Battery is not recognized causing an “X” to appear in the battery icon in the Finder menu bar. Battery will not charge when computer is plugged into AC power. Battery exhibits low charge capacity/runtime when using a fully charged battery with a battery cycle count (as shown in System Profiler) of less than 300. Battery pack is visibly deformed. Note: If your MacBook or MacBook Pro battery does not have any of the symptoms noted above, your battery does not need to be replaced.

Apple said that if the battery is eligible for replacement, customers will receive a new battery free of charge, even if the MacBook or MacBook Pro is out of warranty.

For MacBook and MacBook Pro systems with Intel Core Duo processors, this program extends repair coverage on the battery for up to two years from the date of purchase of the computer.