Apple powermac g3 blue.white Service Manual

 

 Troubleshooting

General/Power Supply Verification - 22

 

1. Plug in a known-good power cord into the back of the 

computer. 

 

 Do not turn on the computer.

 

 For the next steps, refer to Figure 1 to identify the pins 

indicated.
2. Connect the black lead of the volt meter to pin 16 of the 20-

pin power supply connector. Connect the red lead of the volt 

meter to pin 9 of the power supply connector. The volt meter 

should measure approximately +5V.
If you do not get a reading of +5V, re-check the volt meter 

connections and measure the voltage again. If voltage is still 

not present, replace the power supply; otherwise, go to the 

next step.
If you do measure +5V on pin 9, the power supply is likely OK. 

Go to the next step for further verification.

 

Pin 20  +5V
Pin 19  +5V
Pin 18  GND
Pin 17  GND
Pin 16  GND
Pin 15  GND
Pin 14  [Power On]
Pin 13  GND
Pin 12  -12V
Pin 11  +3.3V

+12V Pin 10

+5V TRKL Pin 9

POK Pin 8

GND Pin 7

+5V Pin 6

GND Pin 5

+5V Pin 4

GND Pin 3

+3.3V Pin 2
+3.3V Pin 1