PowerBook G4 (15-inch FW800) Troubleshooting - 25
Hardware Symptom Charts
Half keyboard is illuminated.
1. Check the keyboard backlight cable connection to the trackpad flex cable and the
trackpad flex cable connection to the logic board. If the connections look good, change
the top case.
Microphone
The microphone is not working
1. Check the Sound system preference pane and verify the selection under the Input tab
is for the built-in microphone.
2. Check the signal level and level meter and adjust the gain.
3. Reset PRAM (Press the power button, then hold down the Option-Command-P-R
keys until you hear the startup chime at least one additional time after the initial
startup chime).
Warning: Resetting the PRAM will permanently remove a RAM disk, if present
and all of its contents. You will also need to reset the date and time (using the
Date & Time system preference pane).
4. If there is no sound output from the internal speaker as well as the microphone not
working, verify cable connections.
5. Replace the speaker assembly.
6. Replace sound/DC-in board flex cable.
7. Replace the sound/DC-in board.
8. Replace the logic board.