The Power Mac G4 system freezes during normal operation.

This article covers repair procedures for authorized service providers on selected Apple products, but we have published them in the Knowledge Base for the general public for educational purposes. At this time, there are a limited number of repairs that a customer can perform and these are covered under the customer installable parts program http://www.info.apple.com/installparts . If you have not been authorized to perform these procedures, please contact Apple (800-APL-CARE in the USA) or your local authorized service provider to schedule a repair.

Symptom

The Power Mac G4 system freezes during normal operation.

Products affected

• Power Mac G4
• Macintosh Server G4

Solution

DANGER! This procedure exposes you to high voltages that can result in death or serious injury. DO NOT ATTEMPT THIS PROCEDURE IF YOU HAVE NOT BEEN CERTIFIED AS AN APPLE-AUTHORIZED TECHNICIAN.

1. Boot with extensions off by holding down the Shift key during startup. To isolate the problem, use the Extension Manager to add the system extensions and control panels back one at a time, starting up the system after each addition.

2. Perform a clean install of system software with the system restore CD that came with the computer.

3. Reset the logic board.
- Power Mac G4 (AGP Graphics/Gigabit Ethernet): refer to article 95037: " Power Mac G4 (AGP Graphics/Gigabit Ethernet): Resetting the PMU on the Logic Board ".
- Power Mac G4 (PCI Graphics): refer to article 95066: " Power Mac G4 (PCI Graphics): Resetting the Logic Board ".
4. Remove all third-party hardware from the computer, including RAM, PCI cards, hard drives, external USB devices, and FireWire devices. Also remove any third-party drivers. Reinstall one at a time, starting up after each addition.

5. Run MacTest Pro in loop mode to verify the remaining Apple hardware.

6. Replace the logic board.

7. Replace the processor module.