Powerbook G4 won't boot install disk

Yes, if it's 10.4 or higher. 🙂

Then do this:

Booting From An OS X Installer Disc

1. Insert OS X Installer Disc into the optical drive.
2. Restart the computer.
3. Immediately after the chime press and hold down the "C" key.
4. Release the key when the spinning gear below the dark gray Apple logo appears.
5. Wait for installer to finish loading.

Not at the moment, but I'll mull & watch this thread.

Yeah, only time I had to call Apple was after the help period was over, but I bet a call wouldn't do much good anyway, when I did they told me to do all the steps exactly as I'd already done dozens of times. 😟

Did you ever get it to boot from the AHT disc & run an extended HW test?

Insert the one that says AHT on it, (I think), then boot up holding the Option/alt key down, see if AHT is shown as a boot choice.

Does the computer start up from the Leopard 10.5 retail install DVD?
Reading through the older posts, I see you say you've lost this DVD.
If you are within driving range of a real Apple Store with Genius bar,
you could call ahead to set an appointment to have someone look in
to the computer, where they could attempt to boot it from a 10.5 DVD.

Also, a call into Apple Support/AppleCare can get their attention,
if you are willing to pay the per incident fee for that one issue.

If so, you may be able to run a few checks and repairs from there, on
the system as it is; to see if there is some other problem in the Mac
that may require other action before the drive can be secure erased
for a fully-new installation to take place.

The booted Disk Utility version can allow you to attempt a 'repair disk'
as well as 'verify disk' and a few other tools in Disk Utility can be used
to secure erase, partition map, reformat and other tasks.

There is a possibility the original restore/install DVD disc is damaged.
The PowerBook G4 and iBook G4 were similar in the last G4s with
DVD software sets had the A.H.T. & Install software on the same DVD.
And the instructions on how to use either one, is on the face of the disc.

Not sure if there was some update to the computer which may have
affected the hardware, so the original DVD install won't boot the Mac;
but there may be something else going on in the computer; so try &
see if some actions can be taken with the 10.5.x retail Leopard DVD.

(Since your signature line suggests this later OS X is what's running in it.)

There may be a need to consider retail DiskWarrior to try & fix some
hard drive issues, such as Directory corruption or other failings. Usually
a complete secure erase (at least one-pass, writes zeros over content)
can help remove bad artifacts on the read/write sections of the hard
disk drive; so a later reinstall will find a clean place to run in there.

{Sometimes, odd things can be done to try to get a computer to boot
the discs that something prevents them from using; and they seem
so unrelated to the possible cause of the problem. A PRAM/NVRAM
reset, a PMU reset, and chanting with incense. Voodoo? It may work.}

Hopefully the matter is just something you can fix without hard parts.

Good luck & happy computing! 🙂

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