Powerbook G4 won't charge battery or run with power adapter plugged in.

It sounds to me as if your battery or powerbook is the problem.

If you remove the battery and leave the ac adapter plugged into the laptop, will the computer run off the adapter? If so, that would indicate to me that the battery has probably reached the end of it's lifespan and should be replaced.

If the computer won't even run on the adapter, but the adapter works on other powerbooks, then the charging/power circuits in the laptop are suspect and the computer should probably be seen by a service technician.

Here is a link to an Apple support article about troubleshooting power adapters:
http://docs.info.apple.com/article.html?artnum=302461


TiBook G4 1G, PMac G4 dual 1G, MacPlus Mac OS X (10.4.4)

<< the power adaptor and battery work on a duplicate machine but not on this one. >>

Since, as you say, the power adapter and battery work on a duplicate machine, this suggests a problem with the failed PowerBook itself.

It may be an issue with the PMU... or a problem with the power connecting port... or perhaps some other problem.

Give this KBA a read and see if it might help:
Resetting the PowerBook PMU

If not, it may be time to send the computer in for service, unless someone else can post other suggestions or your research leads to another answer.

TiBook G4 1G, PMac G4 dual 1G, MacPlus Mac OS X (10.4.4)

Hi, Marshall. With no power being supplied to the Mac for several months, not only has your main battery gone flat (and may never again be able to take a charge), but your internal backup battery has also gone flat. A Tibook with a dead backup battery generally will not start up at all, even with AC power connected.

Try this: remove the main battery and leave the AC power adapter connected overnight in an attempt to recharge the backup battery. If the Powerbook won't start in the morning under AC power, the backup battery is shot, has lost the ability to be charged, and must be replaced.

If the PB starts up in the morning on AC power, set the date and time correctly, shut the computer down, insert the main battery, and allow 48 hours with AC power connected in an attempt to charge the main battery. Then disconnect the AC adapter and try to start up under battery power. If that doesn't work, and no lights or only one flashing light appear when you press the power-indicator button on the battery, you'll have to replace the main battery.

http://www.apple.com/batteries/notebooks.html

Since the battery is new and the adapter works with other laptop computers... and the laptop won't run on the adapter...
... it sounds like a hardware failure of some sort in the laptop... perhaps the adapter port has been damaged internally.

Unless someone else can suggest an OS issue or some other tip to get the PMU or power/charging circuits reset, I would have the computer serviced.



TiBook G4 1G, PMac G4 dual 1G, MacPlus Mac OS X (10.4.4)

I am having the same problem with a PB G4 Titanium, the power adaptor and battery work on a duplicate machine but not on this one. We have not started it up in quite some time, matbe 6-12 months - long story. Since the battery has discharged completely could this have effected the power supply or any other critical items?
M. Berenson

Also, you might take a look at this article re: resetting the Power Management Unit (PMU) in your laptop:

http://docs.info.apple.com/article.html?artnum=14449