Powerbook g4 15 not turning on

The Powerbook G4 power button functions like a reset button if you hold the power button in for a few seconds until the computer powers down.

1. Hold the power button in for a few seconds (until you see the screen turn off/go black and hear the fans & hard drive stop spinning).
2. Press the power button again to turn your computer on.
3. If you have more trouble, you may need to boot in Safe Mode or "perform a Safe Boot":
   Press and hold down the "Shift" key immediately after you hear the start-up tone. Release the "Shift" key when the gray Apple icon appears on the screen.

Use the install discs that came with the machine. Insert the disc 1, shut down the machine, turn it back on and press and hold the option key until the DVD icon shows. Then click on the icon and then click on the right arrow. When the disc boots you need to go to the top and find the disc utility folder. Then select reset password. Then choose restart.

Also, check your RAM bay port to see if one of the RAM boards came dislodged and is not inserted correctly. Could also be one of your RAM boards is not compatible or one of the RAM boards is defective.

1. Let it spin for a while and see if it eventually gets to the desktop. Sometimes this will work.
2. Insert your Mac OS install disk, restart your computer (if you need to force it to quit first, push and hold the power button until it shuts off). Then when you restart, as soon as you hear the famous mac chime, press and hold the C key until the Mac OS disk starts to load the system on the disk. Once it reaches the install window, don't launch the install, but go to the top menu bar and locate the Disk Utilities App and launch it. Run a Verify, Repair and also a Repair Permissions. Once done, shut down and restart without holding the C key. You should be good to go.
These powerbook 15" models are awesome... keep it hummin!

Customer forgot password
If the customer forgot the password for the computer:
1. Insert the Software Install and Restore DVD.
2. Restart the computer while holding down the C key on the keyboard.
3. When the installer appears, chose Reset Password from the Installer menu
4. Follow the on-screen instructions.


Here is the link to the user manual and below that is the factory service manual...

http://manuals.info.apple.com/en_US/PowerBookG4_15inch1GHz-867MHzGettingStarted.PDF

http://tim.id.au/laptops/apple/PowerBook%20G4%20(15-inch%20FW800).pdf

Computer cannot find operating system files. Start up from Install Disk or Utility disk and re-install system. Hold down C key while starting from disk.

Resetting PRAM and NVRAM

1. Shut down the computer.
2. Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.

Your computer's PRAM and the NVRAM are reset to the default values. The clock settings may be reset to a default date on some models.
If I could be of further assistance, let me know. If this helps or solves the issue, please rate it.
Thanks, Joe


I’m happy to assist further over the phone at https://www.6ya.com/expert/joe_8b8c2cd6ce148309

Do you have any external harddrive attached to it? If so, remove it before restarting. Try to start it up in safe mode by holding the Shift button down at startup: http://support.apple.com/kb/HT1455

you could try resetting your pram..?

Resetting PRAM and NVRAM

1. Shut down the computer.
2. Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.

Your computer's PRAM and the NVRAM are reset to the default values. The clock settings may be reset to a default date on some models.
Resetting PMU on PowerBook or iBook computers In some troubleshooting situations, if resetting PRAM does not resolve an issue, resetting the PMU may be the next appropriate step. For information on when this is appropriate and for instructions on how to reset the PMU in your PowerBook computer, see Resetting PowerBook and iBook Power Management Unit (PMU).

pull the battery out, put it back in, plug the mac in, and hold down the power key till u hear the chimb