Well, I had to bring in my iBook to a service center and they replaced the DC-in board which was somehow broken. Because you regularly plug in and unplug the power cord, this is a part which is very sensitive to failure.
Repairing it isn't cheap: I paid about 150 euros, which comes down to...
Recently, the battery of my iBook G4 (OS 10.4.2) stopped charging. The light on the power cord does not change to orange, but remains green. With the power cord plugged in, the battery fortunately does not drain.
I tried several things: I did reset the PMU (power management unit) with no...