iMac G4 won't boot into target disk mode

read this article , as i assume the open firmware password is enabled so it wont allow target disc mode
http://support.apple.com/kb/ht1661

 

it could , but it could even be this problem as it describes exactly your problem

http://support.apple.com/kb/TA25584

i there is still a operating system on the mac just go into system preferences and select target disc mode and see what happens


just a interesting bit in a article about that problem ::

When you install a new optical drive, you'll want to set it up as "Master" if it's a Pioneer 105 or other iDVD-compatible drive, and the hard drive as slave. (Setting the drives to "Cable select" will result in the same setup.) (Note: generally with Macs that have both HD and Optical drive on the same cable (only one IDE bus), they have the HD set to Master. I'd Suggest NOT changing the Hard Drive Jumper setting - look at the old Optical drive you're removing and use the same jumper setting on the new drive that replaces it. (Jumper settings usually marked MA/Master, SL/Slave, CS/Cable select - normally iMac G4 optical drives are Slaves IIRC.)
A reader also mentioned that when using Firewire Target Disk Mode to transfer data to his new iMac G5 didn't work if the iMac G4's HD was set to slave, referring to an Apple kbase doc FireWire Target Disk Mode: Target Computer Shuts Down at Startup which said a Hard Drive must be on "Bus 0", but the iMac G4 has only one IDE bus (not two as many other Macs have). "Bus 0" isn't the same as Drive "ID 0" (master). (Drive -ID's- are 0 for Master, 1 for Slave.) OS X 10.2.4 had a problem not recognizing Superdrives if they were set to slave (noted back then in the news page) but OS X 10.2.5 fixed that issue.
In the past I have seen FW target disk mode *not* mount a Hard Drive set to slave on a system where I had 2 Hard Drives (one master, one slave) on the primary bus, although that may no longer be a problem for later macs, personally I'd set the new Optical drive to the same setting as the drive you're removing.
Starting with the MDD G4 towers, Apple suggests cable select for all drives, HD or optical. This automatically makes the end drive on the cable a master and the drive on the 2nd connector a slave.-Mike)

i hope that helps as i believe someone might have changed the harddrive / or optical drive and jumpered them wrong

 

Will it boot from the optical drive? What happens if you power it up without trying Target Disk Mode?

 

Well, that's a good sign that you're getting the question mark/folder, at least it's not shutting down. Does it spit out all discs?

 

If you have an external firewire drive you could install an os on it and connect that one to the imac.

 

It should (at least may) boot from a USB drive also. My G4 eMac 800Mhz has USB booting.

Has to be OS 9 or 10.4.5 or later.

But Firewire is a better choice.

 

It sure did help!
I googled for ages before I stumbled upon this thread, which exactly described the problem with my iMac G4. You guys made me realize I never checked the jumpers before I put the HDD in! Installing Tiger right now, wohoo! Thanks alot, internet people from seven years ago!

Edit: I now see that the length of my username was a poor choice. Oh well.