A & T Internationale Xserve, Service Source

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Xserve (Late 2006) Troubleshooting — General Information
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Power Supply Verification
To power on, the Xserve’s logic board requires “trickle” power. If the system fails to power on,
first reset the SMC as described in this chapter. If the Xserve still doesn’t power on, follow the
procedure outlined below to determine whether the issue is related to the power supply.
Verify trickle power
Diagnostic LED DS9C4 (5VSTBY) indicates the presence of trickle power required by the logic
board to begin the startup process.
LED DS9C4 should be ON when the power supply is plugged into a good AC outlet, indicating
that trickle voltage is present.
Verify Power Supply Is Providing Power
Diagnostic LED DS9C6 (VR_PWR) indicates that the main power is OK and within regulation.
Plug in AC power cord, and press the power-on button on the front panel.
LED DSC9C6 should be ON when the Xserve starts up, indicating that the main power is OK and
within regulation.
If you cannot verify these LEDs are on, try replacing the power supply with a known-good one.
If you are working with an Xserve with two power supplies, try removing one and test one at a
time to determine which one may have the issue. Also try the same known-good power supply
in each power supply bay, to see if the issue is related to a single bay or not.
If you try a known-good power supply in both bays and you are still having power issues, try
replacing the power distribution board.
Internal Sensor Locations
Xserve (Late 2006) includes many built-in sensors that report on hard drives, internal
temperature, fan status/failure, and power status/failure. These sensors allow you to monitor the
Xserve’s operation.
For more detailed information, see the “Appendix” at the end of this manual.