Troubleshooting Symptom/Cure Tables: System Problems After Startup - 37
Can’t Wake From Sleep
The computer cannot be brought out of “sleep” mode by pressing a key on the key-
board. The problem is usually evident by a black screen and a pulsing amber LED.
Possible Cause Possible Fix
PMU Press the PMU chip on the logic board with the AC
power cord disconnected. (See “The PMU Chip” and
“Resetting the PMU on the Logic Board” mentioned
earlier in this chapter.)
Connect the power cord and power on the system again.
Do you have power to the system now?
Yes: Test the unit with MacTest Pro and return the
computer to the customer.
No: Plug in the AC power cord and reset the PMU chip
again. Do you have power to the system now?
Yes: The battery is likely bad, check the battery.
No: Go to the next step.
Bad keyboard Try a known-good keyboard.
Corrupted PRAM Reset the PRAM by holding down the Option–Command–
P–and R keys
Software Conflict Reinstall System Software. You must use the system
software that came with the unit in order to get the
correct version of Mac OS. Note: If the computer
sleeps while connected to the Internet, and is running
Mac OS 8.6 or Mac Os 9.0, download Apple Audio
Update 1.3 from the Apple Software Update page.
Bad logic board Replace the logic board.