mg.to

Matt from the ThinkPad mailing list found this out the hard way: Do not install the latest Embedded Controller Update on your ThinkPad if you have a non-IBM replacement battery, or your machine will no longer work on battery power. This new firmware update checks the battery status in a way that fails with non-IBM batteries.

The version number for the bad update varies for different models, but check the release notes for a phrase like “Enhancement of the battery control.”

The problem affects at least the A30/A30p and A31/A31p models, and possibly others.

Matt’s report is here:

A30/p Embedded Controller Update = Danger, Will Robinson!

Adding insult to injury, the way to fix the problem is to downgrade to the previous version of the Embedded Controller firmware, but you to do this, you need:

1. A copy of the previous version for your machine. (And where do you get that?)
2. A floppy drive. (The non-diskette version doesn’t work.)
3. A charged battery—which means a fresh IBM battery, because your ThinkPad no longer trusts the non-IBM battery!

I’m a huge ThinkPad fan; I just hope this battery incompatibility is an inadvertent bug and that IBM will fix it quickly.