Apple xserve Service Manual

6 - Xserve Troubleshooting

 General Information

To power on, the server’s logic board requires a “trickle” power of +5V. If the system fails to 

power on, first reset the PMU. Then follow the procedure outlined below to determine 

whether the problem is related to the power supply.

Note: To verify the power supply, you need a volt meter. When connecting the volt meter 

leads to specific pins, make sure the power supply remains securely plugged into its 

connector on the logic board.

The following figure shows the pins and voltage on the server’s power supply connector, 

as viewed from above when it is connected to the logic board.

 

1.

Plug a known-good power cord into the server. Do not turn on the server.

2.

Connect the black lead of the volt meter to pin 14 of the power supply connector; 

connect the red lead of the volt meter to pin 1. The volt meter should measure 

approximately +12V.

If you do not get a reading of +12V, recheck the volt meter connections and measure 

the voltage again. If voltage is still not present, replace the power supply.

If you do measure +12V on pin 1, the power supply is likely OK. Go to the next step 

for further verification.

3.

Start up the server by pressing the power button on the front panel.

If the server starts up normally, the power supply is OK. If the server does not start 

up normally, go to the next step.

Pin 1  +12VDC

Pin 2   GND

Pin 3

+12VDC

Pin 4

+5VDC

Pin 5

+5VDC

Pin 6

+5VDC

Pin 7

+3.3VDC

Pin 8

+3.3VDC

Pin 9

+3.3VDC

Pin 10 -12VDC

Pin 11 Power On

Pin 12 +5VSB

+12VDC Pin 13

GND Pin 14

GND Pin 15

GND Pin 16

GND Pin 17

GND  Pin 18

GND Pin 19

GND Pin 20

GND Pin 21

GND  Pin 22

GND Pin 23

GND Pin 24