Power Supply Test - Sun Microsystems Sun Ultra 60 Service Manual

b. Type probe-scsi.
If the hard drive responds correctly to probe-scsi, the message identified in Code
Example 4–7 is displayed. If the drives respond and a message is displayed, the
system SCSI controller has successfully probed the devices. This is an indication that
the motherboard is operating correctly. If one drive does not respond to the SCSI
controller probe but the other does, replace the unresponsive drive. If one hard drive
is configured with the system and the probe-scsi test fails to show the device in
the message, replace the drive. If the problem is still evident after replacing the hard
drive, replace the SCSI drive bay (see Section 8.3 "Hard Drive Bay With SCSI
Assembly" on page 8-7). If replacing both the hard drive and the SCSI drive bay
does not correct the problem, replace the motherboard.
4.4

Power Supply Test

The section describes how to test the power supply. Figure 4–1 and Table 4–2 identify
power supply connector J2901. Figure 4–2 and Table 4–3 identify power supply
connector J2902. Section 4.3 "Disk Drive or CD-ROM Drive Failure" on page 4-3 and
Table 4–4 identify power supply connector J2903.
1. Power off the system.
2. Remove the side access cover.
See Section 7.1 "Removing the Side Access Cover" on page 7-1.
3. Slide the power supply from the chassis enough to expose connectors J2901
through J2903.
4. Power on the system.
5. Using a digital voltage meter (DVM), check the power supply output voltages
as follows:
Note -
the motherboard.
a. With the negative probe of the DVM placed on a connector ground (Gnd)
Sun Ultra 60 Service Manual ♦ March 1999, Revision A
4-4
Power supply connectors J2901 through J2903 must remain connected to
pin, position the positive probe on each power pin.