User Guide

8 - Power Mac G4 Cube Troubleshooting
Symptom Charts
Symptom Charts
How to Use the Symptom Charts
The Symptom Charts included in this chapter will help you diagnose specific symptoms
related to the product. Because cures are listed on the charts in the order of most likely
solution, try the cures in the order presented. Verify whether or not the product continues
to exhibit the symptom. If the symptom persists, try the next cure.
Note: If a cure instructs you to replace a module, reinstall the original module before you
proceed to the next cure.
Important: The only way to shut off power completely to the computer and display is to
disconnect their power plugs from the power source. Make sure the power cords to the
computer and display are within easy reach.
Startup
No apparent power (no sound and power LED is not lit)
1. Verify the power outlet is good.
2. Replace the power cord.
3. Reset the logic board. Refer to "Resetting the PMU on the Logic Board" in this
chapter.
4. Check for trickle voltage on the power adapter connector. Refer to "Power Adapter
Verification" in this chapter. If verification fails, replace the power adapter.
5. Disconnect external devices, including the monitor, and start up the computer.
6. Remove internal cards and start up the computer.
7. Disconnect internal hard drives from the logic board and start up the computer.
8. Reseat the DC-to-DC board in its connector.
9. Check the modem connector. If the connector has any bent pins, replace the logic
board.
10. Replace the logic board.