Power problem on MacBook Pro

I've noticed my MacBook Pro starting to put itself to sleep, no warning, when the battery hits around 27-30%.
Ian McCall wrote on :

I've noticed my MacBook Pro starting to put itself to sleep, no warning, when the battery hits around 27-30%. It's immediately able to wake again, but quite often when I do the battery reads 0%. However the machine will happily keep running for quite a while - the battery clearly isn't on 0% for real (I'm using it now for example, with 0% showing and having been showing for a while).

I've tried resetting the PMU - any other ideas? Any calibration tricks I can use?

Cheers, Ian

zoara replied on :

On Fri, 23 Mar 2007 09:02:22 +0000, Ian McCall wrote:

I've noticed my MacBook Pro starting to put itself to sleep, no warning, when the battery hits around 27-30%. It's immediately able to wake again, but quite often when I do the battery reads 0%. However the machine will happily keep running for quite a while - the battery clearly isn't on 0% for real (I'm using it now for example, with 0% showing and having been showing for a while).

I've tried resetting the PMU - any other ideas? Any calibration tricks I can use?

Have you done the "let it run to (complete) zero, charge it up to full, rinse, repeat" trick? When the bettery gets so low that it sleeps, you have to leave it unplugged until it dies completely.

It's a bit voodoo but I've fixed one (old) machine that way.

-z-
Ian McCall replied on :

On 2007-03-23 09:36:15 +0000, zoara me17@redacted.invalid said:

Have you done the "let it run to (complete) zero, charge it up to full, rinse, repeat" trick? When the bettery gets so low that it sleeps, you have to leave it unplugged until it dies completely.

Nope, will give that a go this evening then.

It's a bit voodoo but I've fixed one (old) machine that way.

I seem to remember being advised to do that with a Powerbook too, now you come to mention it.

Cheers, Ian

Jaimie Vandenbergh replied on :

On Fri, 23 Mar 2007 09:02:22 +0000, Ian McCall ian@redacted.invalid wrote:

I've noticed my MacBook Pro starting to put itself to sleep, no warning, when the battery hits around 27-30%. It's immediately able to wake again, but quite often when I do the battery reads 0%. However the machine will happily keep running for quite a while - the battery clearly isn't on 0% for real (I'm using it now for example, with 0% showing and having been showing for a while).

I've tried resetting the PMU - any other ideas? Any calibration tricks I can use?

http://docs.info.apple.com/article.html?artnum=86284

Cheers - Jaimie