Troubleshooting

General/ Logic Board Troubleshooting - 20

 

 

DS6 = Ultra ATA bus activity

DS6 indicates Ultra ATA bus activity.

DS7 & DS8 = Power Indication

In a working unit, these LEDs should be in sync with each other: both on or both off. If one LED is on and the other is off, there is a problem.

DS9 = CPU Bus Request

When illuminated, this LED indicates that the CPU is requesting the bus. This LED will rarely glow as brightly as the others (like the Ultra ATA LED) given that the CPU is not always requesting the bus, and when it does, the period of time is short. As a result, you may need to watch this LED much more carefully than the others to tell if there is activity. If this LED is ever on continuously and bright, then the system is troubled and likely hung.

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Apple G4 manual DS6 = Ultra ATA bus activity, DS7 & DS8 = Power Indication, DS9 = CPU Bus Request