View Full Version : iBook G4 12" A1133 Not Powering Up/Power not Getting to PMU?

Marina Grainger
Jan 5, 2010, 07:37 PM
Hi, I've inherited an iBook G4 12". Model A1133. It came with a partially charged battery and a known power issue. Initially with the battery partially charged (on another iBook), the machine turned on ok. The battery was not charging, according to the About this Mac and the Coconut Battery application, although the light on the AC adaptor was amber. As the battery became flat, the iBook was no longer able to be turned on.

I have reset PMU, PRAM, Opened the Firmware and reset the NVRAM, reseated the battery and tried a host of things suggested on this forum and others to no avail.

I have also replaced the DC-in board (no difference, so put the old one back in) and tried a different power adaptor.

The battery is as flat as a tack (now occasionally flashing one light when button is pressed) and now there is no chime, fan noise except for an occasional sound which sounds like the hard drive starting then stopping (very faint sound though) when I try to power up the iBook.

I was hoping to get an external battery charger to charge the battery as I don't have a spare charged one nor access to a similar working iBook. I live in Australia and have been unable to find one online here.

The other thing I have heard on two forums, is that this iBook doesn't have a PRAM battery and therefore cannot start without a powered battery in place. If this is the case, then the issue may be that of just the power not being delivered to the PMU?

At wits end :confused:. Any advise gratefully accepted.


Jan 6, 2010, 09:29 AM
Have you tried powering on without the battery in place just running off a/c power? If that doesn't work it sounds like the logic board on that ibook is toast and you should sell it for parts or fix it up. Or if its very poor condition the garbage can.

Jan 7, 2010, 05:07 AM
You are right that the iBook doesn't have a pram battery, at least the 12 inch one i'm sure. It shouldn't affect startup though. I remember being able to start my old iBook without the battery for a week or so when my old one died and I had to replace it (it pained me to pay more than $100 for a battery for a 5 yr old laptop).

Marina Grainger
Jan 7, 2010, 10:05 PM
Thanks matthewscott661.

I am getting power into the battery as the light changes from green to amber when the battery is seated. I am thinking now the problem is two-fold. Dead battery (it's never been changed) and the AC problem so it can run without the battery.


Jan 7, 2010, 10:29 PM
I remember being able to start my old iBook without the battery

have you tried this yet? Take the battery out and try to start it up.

If that works it's most likely the battery.

IF it doesn't it may be the charger or the Logic Board... the Green and Amber lights are feed back from the Logic Board. Have the charger checked out by a professional.

Marina Grainger
Jan 7, 2010, 11:38 PM
Thanks rjphoto for the suggestion.

I did try starting it without the battery, it still didn't work.

I have two charges, both of which work.

Looks like a logic board issue?

Has anyone heard of a supercapcitor in the iBook? Could this cause PMU issues?