Service manual

16 Troubleshooting
Example 2–3 shows the system exerciser display for the SCSI-A bus.
There is one line for the status of the SCSI-A controller on the system
module, and one line for each of the drives installed on the SCSI-A bus.
The status of the SCSI controller is next to the SCSI-A mnemonic (first
line), and the status of each drive is listed under the controller’s code
(separate line for each drive).
7 80A0 SCSI−A 6000.0001
2200.0001
3200.0001
5300.0001
3 0000 0 00:05:26
RZ23 disk drive
RZ23 disk drive
RX23/SCSI adapter
Example 2–3 System Exerciser Results for the SCSI-A Bus
If an Error is Detected
If there are any question marks (?) on the SCSI controller’s status line,
the SCSI controller is probably faulty and must be replaced.
If there are any question marks on a drive’s status line, the problem could
be in either the drive, the SCSI bus cabling, the SCSI bus terminator,
or the SCSI controller. For example, an error that is listed in the drive’s
code may be a data transfer error and does not isolate the problem to the
device itself; it may still be in the SCSI controller.
2.3.2 Power Connector Pinouts
Figure 2–1 illustrates the pinout locations for the power connector which
are located on the system module. See Table 2–3 for system module power
connector voltages.