[neal1973]

For some reason, as soon as I remove the powerlead - or it pulls out - my powerbook G4 1.67 shuts down after about 1-2 seconds.

The battery is 6 months old - and it worked for a while with no problems - and it is charged to 96%.

When I re-boot with powerlead attached, I have to reset the internal clock to today's date.

I vaguely remember reading something about this being due to a worn-out internal battery, which affects power management???

Does this sound right?

If so, is it easy to buy/fit a new internal battery? Does anyone have any links to instructions?

Any other ideas?

Many thanks in advance for any help I can get.

Cheers, Neal

[Jolt21]

Does your screen fizzle out right before the unit shuts down? I actually have a very similar problem, but mine last anywhere from 1 min to 10 min. It will eventually fizzle out and die if unplugged, but the length of time varies.

[analogika]

have you reset the PMU?

http://support.apple.com/kb/HT1431


It is, however, very likely that your internal backup battery is empty.
Instructions for replacing: http://www.ifixit.com/Guide/Mac/Powe...ry/64/5/Page-1

[Judge_Fire]

I have the same G4 PB and its PRAM battery appears to be gone, too. Coincidentally, Apple released new MacBooks and somebody already placed an order...

Regardless, I used to have an issue with filling up the actual main battery on this Mac, too. For additional annoyance, when I plugged it in, it took a few minutes before it had enough juice in the battery to agree to start - it would not use direct power.

Turns out, I was using my wifes 12" PB's power brick, which gave me less watts than needed. Thanks to someone here, I realized that was the case, and we promptly sorted out our power sources.