The battery was dead, and the power supply functional on another machine.

Mi Problema

I searched for a simple solution. And, I found it, by iFixit.

Mi Solución

There were two possibilities. The first was a defective logic board. In this case, the cost becomes unreasonable. The iBook was good for recycling. Or, DC-in-Board was defective. There was no way of knowing which of the two. It was like a game of heads or tails, $30 versus $400. So, as the DC-in-Board was most likely the culprit, I made the jump.

Mi Consejo

The instructions are very clear, and the difficulty level is very acceptable. It is important to identify the parts mounted on a sheet of paper, with the Scotch tape and the number of the step. Everything is fine now.