Stubborn powerbook battery won't charge

July 30, 2007 10:49 AM

The battery in my G4 Powerbook won't charge, and I am a long way from any technical help!

I have a Powerbook G4 15 inch 1.67. The battery is about a year old and is not one of the recalled ones. I left my computer in hibernate mode while away for a week and when I came back the battery was drained, which is not uncommon. However, now the battery will not take a charge at all. Some relevant symptoms:
- menubar indicator shows 0%,"calculating until full", which never changes
- the lights on the battery do not blink
- depressing the battery button produces the flickering green "battery empty" signal
- the computer will only boot if the PMU is reset, but will soft reboot without that step
- it runs fine with the battery in or out, but of course dies immediately the power cord is pulled out

I have googled around and done the PMU reset and also tried:
command-option-p-r (reset PRAM) (whatever that is) and
command-option-o-f; reset-nvram; set-default; reset-all

One potential confound is I am using an aftermarket power adapter which apparently only puts out 50 watts not the 65 of the stock model. This is preventing me from updating the firmware - it demands 65 watt adapter. However, I have never had a problem with this adapter and it shows as charging.

Sytem profiler:

Battery Information:

Battery Installed: Yes
First low level warning: No
Full Charge Capacity (mAh): 3421
Remaining Capacity (mAh): 0
Amperage (mA): 0
Voltage (mV): 9831
Cycle Count: 293

AC Charger Information:

AC Charger (Watts): 50
Connected: Yes
Charging: No

So, any ideas, hive mind? Software, hardware, battery itself? I am in a town (pop. 800) with internet for one day, then back into the bush for three weeks, where I would like to have use of this battery!

posted by Rumple to computers & internet (5 comments total)

There are three ways to reset the PMU. Have you tried them all?
PowerBook G4 (15-inch 1.67/1.5GHz), PowerBook G4 (17-inch 1.67GHz), PowerBook G4 (15-inch Double-Layer SD) and PowerBook G4 (17-inch Double-Layer SD)

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.


PowerBook G4 (12-inch)
PowerBook G4 (12-inch DVI)
PowerBook G4 (12-inch 1.33GHz)
PowerBook G4 (12-inch 1.5GHz)
PowerBook G4 (15-inch FW 800)
PowerBook G4 (15-inch 1.5/1.33GHz)
PowerBook G4 (17-inch)
PowerBook G4 (17-inch 1.33GHz)
PowerBook G4 (17-inch 1.5GHz)

1. If the computer is on, turn it off.
2. Reset the power manager by simultaneously pressing and then releasing Shift-Control-Option-Power on the keyboard. Do not press the fn (Function) key while using this combination of keystrokes.
3. Wait 5 seconds.
4. Press the Power button to restart the computer.


PowerBook G4 (DVI) and PowerBook G4 (1 GHz/867 MHz)

1. If the computer is on, turn it off.
2. Disengage the two keyboard latches located between the Esc and F1 keys, and the F11 and F12 keys. (You may also need to disengage the keyboard locking screw located between the F5 and F6 keys.)
3. Lift the keyboard. To ensure no harmful static electricity is transferred to the computer, properly ground yourself before performing this procedure.
4. Press and release the reset button located on the upper right side of the logic board near the power button, shown here.
5. Wait 5 seconds.
6. Press the power button to restart the computer.
posted by Gungho at 11:16 AM on July 30, 2007

Any chance that there is corrosion on the battery contacts?
posted by bottlebrushtree at 11:16 AM on July 30, 2007

This sounds like a case of a (physically) bad battery. However, before I'd go buy a new one, I would make sure I had tried the following:
- Resetting the PMU
- Doing a reset-all in Open Firmware
- Resetting the PRAM
- Removing / Re-inserting battery repeatedly and cleaning the battery contacts sdfsd

Just for kicks, you might also try uninstalling any software you recently added: a poster in this thread claims that disabling a desktop picture rotation utility he had installed restored his battery-charging abilities. Doesn't make any sense, but you never know!
posted by dyslexictraveler at 2:56 PM on July 30, 2007

using a power adapter that's less than the one that shipped with it will probably mean it won't charge when it's actually turned on. (older iBook/titanium PowerBook adapters were 45 watts - they worked just fine with newer ones, but your battery wouldn't charge if the system was on. same with using a 60watt MagSafe on your new MacBook Pro. your machine shipped with a 65watt adapter.) your computer may have decided to be picky about it. does it not blink even when the computer is off? (fwiw, only the first of the instructions Gungho posted applies to your computer - the other two are for older PowerBooks.)

I'd probably go ahead and buy a new one if you've got the cash (and can find one) - it'd probably be worth it to have a spare anyway - and/or doing an Archive and Install if you can. (this will preserve your apps and user data but will replace the copy of the OS you have installed.)
posted by mrg at 3:06 PM on July 30, 2007

Thanks everyone. I've tried all the steps and no joy! Nor batteries, in this small town (had a hard time scaring up enough AA batteries yesterday, which gives you an idea). When I'm back in the big smoke I have an old but working battery and will try that, as well as the stock power adapter, and get it figured out. In the meantime, just don't jiggle my powercord!
posted by Rumple at 7:34 AM on July 31, 2007