I have a iBook G4 1.2 Ghz 12". The light on the power adapter regular shuts off, thus forcing my iBook to draw on my battery, even when plugged in. My battery is old, but charges and works. I just replaced the power adapter, the light continues to shut off after a little while. It takes anywhere from 5 to 25 min for the light to go off (it does it both during charging or after battery is fully charged.) To get the computer to recognize the power adapter, I need to unplug it from the wall and re-plug it in. Could this be due to a problem with the DC in? I'm willing to try replacing that, if it might be the problem. But my concern is that this happens intermittently and thus must be the logic board. Thanks for your advice!