Service Manual
6-5
Troubleshooting
6
3.
DC Output:
Refer to Appendix C, “Wiring Diagrams” for more
details on other voltage test points.
■
+5 VDC
±
0.25
■
+12 VDC
±
0.6
■
-12 VDC
±
0.6
■
+40 VDC
±
0.4
■
+78 VDC
±
2% (adjustable from 68 to 102 VDC)
■
-78 VDC
±
2% (adjustable from -68 to -102 VDC)
If you do not measure the expected DC voltages, proceed to the next step,
“Inspecting the power supply fuses.”
If the +5 VDC,
±
12 VDC,
±
78 VDC voltages measure correctly proceed to the
topic “Testing for a shorted DC supply” on page 6-6.
Figure 6-1 Measuring the DC voltages (test points)
Power supply board
7
8
9
10
11
12
1
2
3
4
5
6
+12v
-12v
HVEN
+5v
+5v
+5v
+12v
GND
-12v
GND
PFAIL
+5v
GND
+5v
GND
+5v
GND
CN3
6
7
8
9
10
1
2
3
4
5
+78v
-78v
+40v
+40v
+40v
±
78v
GND
±
78v
GND
+40v
GND
+40v
GND
+40v
GND
CN4
9482-12