Sun Microsystems SUN BLADE 150, Service Manual

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4-4 Sun Blade 150 Service Manual • June 2002
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If the
probe-ide
test fails to show the device in the message, replace the drive
(see Section 7.3, “Hard Drives” on page 7-6). If replacing the hard drive does not
correct the problem, replace the motherboard.
4.4 Power Supply Test
This section describes how to test the power supply. Appendix B shows and
describes the power supply connectors J501.
1. Power off the system, remove the system cover, and attach an antistatic wrist strap
as described in Chapter 5 “Preparing for Component Removal and Replacement.”
2. Disconnect the IDE ribbon cables from the riser board so that you can access
connector J501.
3. Power on the system.
See “Finishing Component Replacement” on page 9-1.
Caution –
With the system cover removed and the system powered on, there is
unprotected access to voltage and energy levels that are potentially hazardous to
equipment and personnel. If you are unsure how to safely proceed, please seek the
assistance of qualified service personnel.
4. Using a digital voltage meter (DVM), check the power supply output voltages as
follows:
Note – Power supply connector J501 must remain connected to the riser board.
a. With the negative probe of the DVM placed on a connector ground (Gnd) pin,
position the positive probe on each power pin.
See Section B.1, “Power Supply Connectors” on page B-2.
b. Verify voltage and signal availability as listed in Appendix B.
5. After you finish testing the power supply, remove the wrist strap, replace the
system cover, and power on the system as described in Chapter 9 “Finishing
Component Replacement.”