Wednesday, December 12, 2007

battery woes

I'm traveling right now and I am taking along my teeny little 12" PowerBook which has been good to me for many years. Only, this time, I upgraded it to Leopard and I think it messed up my battery stuff. (Also, upgrading may not have been a good idea since Leopard heavily uses CoreImage, and this computer doesn't support it. The 12-incher is also the minimum specs for the OS: 867MHz, 640MB RAM, 32MB GeForce 4MX video).

I noticed that it goes to sleep quickly -- say when the battery was drained less than half -- and it charges quickly. This lead me to believe it might be a power management issue, so I rebooted the machine and reset the PMU and PRAM. No luck. Still problems. I decided to "condition" the battery, or drain it all the way and charge it again, but I planned to monitor the battery status with pmset (a mac os x command line utility). Here's it's output:

sid-stamms-powerbook-g4-12:~ sidstamm$ pmset -g pslog
pmset is in logging mode now. Hit ctrl-c to exit.
12/12/07 4:57:20 AM GMT-05:00
Currently drawing from 'Battery Power'
-InternalBattery-0 98%; discharging; 10:00 remaining
12/12/07 4:57:24 AM GMT-05:00
-InternalBattery-0 97%; discharging; 10:00 remaining
12/12/07 5:05:05 AM GMT-05:00
-InternalBattery-0 96%; discharging; 10:00 remaining
12/12/07 5:14:44 AM GMT-05:00
-InternalBattery-0 95%; discharging; 10:00 remaining
12/12/07 5:25:30 AM GMT-05:00
-InternalBattery-0 94%; discharging; 10:00 remaining
12/12/07 5:34:33 AM GMT-05:00
-InternalBattery-0 93%; discharging; 10:00 remaining
12/12/07 5:45:17 AM GMT-05:00
-InternalBattery-0 92%; discharging; 10:00 remaining
12/12/07 5:54:55 AM GMT-05:00
-InternalBattery-0 91%; discharging; 10:00 remaining
12/12/07 6:03:09 AM GMT-05:00
-InternalBattery-0 90%; discharging; 10:00 remaining
12/12/07 6:11:24 AM GMT-05:00
-InternalBattery-0 89%; discharging; 10:00 remaining
12/12/07 6:19:20 AM GMT-05:00
-InternalBattery-0 88%; discharging; 10:00 remaining
12/12/07 6:20:08 AM GMT-05:00 Sleeping...
12/12/07 6:20:08 AM GMT-05:00
-InternalBattery-0 0%; discharging; 0:00 remaining

Notice how it drops into sleep at 88%, and the perceived status drops to zero... I think either this battery is toast, or Leopard destroyed it. (I verified the full/empty statuses by pushing the meter button on the battery itself, watching the LEDs tell me how full it is.)

Anyhow, I'm going to let it try to charge all night, even though it will surely give up. Maybe the Internets will tell me what's going on, or maybe I'll just use it as a portable desktop computer. I'll follow this post up with results from pmset while charging to see what it tells me.

Here's some info from system profiler about the battery as it begins charging:

Battery Information:

Charge Information:
Charge remaining (mAh): 177
Charging: Yes
Full charge capacity (mAh): 20494
Health Information:
Cycle count: 294
Battery Installed: Yes
Amperage (mA): 2079
Voltage (mV): 12250


Mike said...

Hi! I was wondering if you ever resolved this issue. I'm using a 6 year old PowerBook and I've noticed the battery life is somewhat less than I'd like. (It's a 2 year old battery and I use a conditioner once in a while, which seems to help a little.)

I've recently started using console mode instead to see if that helps, but I'm having trouble getting an accurate reading of battery life in text mode.

Sid Stamm said...

@Mike: I never did solve the problem. My trip ended, and I went back to using my newer Macbook. I basically used it as a portable computer that had to be plugged in, which was OK, but not that nice.

If you haven't reset your PMU, you should totally do that, but other than that I'm out of ideas.