Apple PowerBook G3 400 Troubleshooting
The display is on but the keyboard is not functioning as an input device.
The keyboard could be loose, in which case you will have to reconnect the keyboard. You must go through the keyboard repair guide to fix this.
If the reconnection does not work, replacement may be the required course of action. The replacement process is the same in this case.
It is possible that it appears nothing is happening because of a faulty or imperfect display.
The display might be connected poorly, in which case you must follow the display repair guide steps to fix your problem.
If that doesn't fix the problem, the display could possibly be broken. In that case you must also follow the display repair guide steps to fix your problem.
If the computer does not recognized the RAM it may have become disconnected or may be broken.
The RAM might have become loose in which case you will need to follow the RAM repair guide to reconnect the RAM.
If the RAM is broken, it will need to be replaced. You will follow the same steps as before to replace the RAM.
If the sound does not work, the sound card could be defective.
Make sure the volume is up and the computer is not on mute. The proper drivers must also be installed.
If the sound still does not work and software is not an issue, check the speakers and see if they are broken.
If the software and speakers are not the problem, then the sound-card will need to be replaced. Follow the sound card repair guide to replace the broken card.
If information cannot be saved and your previous information cannot be viewed, the hard drive may be broken.
Follow the hard drive repair guide to remove the broken drive and install a new one.