[shabbasuraj]

How do I diagnose/troubleshoot this thing?

Remove the old hard drive, put in a known working hard drive, and it still won't book.

Just black screen.

I hear the HD spinning only when it is plugged in. When I unplug the machine, the HD no longer spins up. Completely dead, despite the fact that the battery is fully charged.

Maybe could be the DC board? As HD only spins when plugged in...

http://www.ifixit.com/PowerBook-Part...Card/IF154-073

So does this mean that the logic board (or some other part of it) is dead.

Tried putting in the supplied boot disc. Optical Drive won't accept the drive. Try holding down C, while pressing the button. Nothing.

edit...
LOL. Found this page.

http://www.ifixit.com/Wiki/PowerBook...roubleshooting

Still interested in hearing from anyone's awesome expertise....

[Waragainstsleep]

Have you reset the PMU? Procedure will vary depending on model. They are all listed on the Apple site.

[shabbasuraj]

Originally Posted by Waragainstsleep 

Have you reset the PMU? Procedure will vary depending on model. They are all listed on the Apple site.

It won't even boot?

[shabbasuraj]

Found info here..
Resetting PowerBook and iBook Power Management Unit (PMU)

I hear the HD spin up for 1 second.. then power cuts out, and the machine turns off.

sux.