Cant Wake From Sleep

The computer cannot be brought out of "sleep" mode by pressing a key on the keyboard. The problem is usually evident by a black screen and a pulsing amber LED.

Possible Cause

Possible Fix


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.

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