Technical information

Symptom Charts / Video -
11
Troubleshooting
PowerBook (FireWire)
No display, but
computer appears to
operate correctly
1. Connect power adapter.
2. Adjust screen brightness using keyboard controls.
3. Verify display cable, inverter board, and I/O logic board
connections.
4. Connect external, known-good monitor.
5. Verify inverter cable is properly connected.
6. Replace inverter cable.
7. Replace inverter board.
8. In the U.S., contact Apple Technical Support.
9. Replace display cable (international only).
10. Replace display (international only).
11. Replace I/O logic board.
An external monitor
connected to the
computer shows
either horizontal or
vertical rolling, or
horizontal or vertical
distortion
1. Try different resolutions in the Monitors control panel.
2. Verify monitor using another computer.
3. Try another video adapter and verify the video adapter has
part number 590-1123 on it.
4. Replace I/O logic board.
Backlight doesn’t
operate; screen is
very dim
1. Adjust screen brightness setting.
2. Verify backlight cable connection is secure.
3. Check display cable and inverter board connections to the I/O
logic board.
4. Verify inverter cable is properly connected and that cable is
good.
5. Verify cables are not pinched or severed.
6. Replace inverter board.
7. In the U.S., contact Apple Technical Support.
8. Replace display (international only).
9. Replace I/O logic board.