Specifications

o 0
J--=!
1.
khtfur
Test pointsare accessiblethroughthetop
ventholesIn
the chaseis after the top
cover has
beenremoved.
Figure4-15. System Unit CPU Board Voltage Tat Fbints
(Modd 400s, 425s, and 433s)
Table 4-4 lists the voltages that the power supplyprovides to the systemunit.
Table 4-4. System Unit hwer Supplj Voltagesand Tolenrncer
(Model 400s, 425s, and 433s)
Voltage (de)
‘1’olerance
+5
4.85
to 5.20 V dc
-5
-4.60 to -5.50
v dc
+9
8.70
tO 9.30 V de
•t 12
11.40 to 12.60 V dc
-12
-11.40 to -12.60 V dc
Continue with Step 4 or Step 5, depending on the result of your voltage checks.
4. If the DC output voltages are not present at the CPU board test points,
perform the followingsteps
A.
B.
If the systemunit has an ISA/EISA backplane, remove the right
side and RFI covers. Check the voltageson the ISA/EISA power
distribution cable on the ISA/EISA backplane as listed in
Figure 4-18. If the voltagesare present, re lace the CPU board. If
B
the voltages are not present, goon to step .
Check the ac outlet for wer with a voltmeter. If the ac outlet
1’”””
power is inrmrect, an e ectnclan must correct it.
4-24 Troubleshooting