IBM RS/6000 44P 270 Service Manual page 50

Symptom
No codes are displayed on the operator panel
within a few seconds of turning on the
system. The operator panel is blank before
the system is powered on.
The SMS configuration list or boot sequence
selection menu shows more SCSI devices
attached to a controller/adapter than are
actually attached.
32
Service Guide
Action
Reseat the operator panel cable. If the problem is
not resolved, replace these parts in the following
order:
1. Operator panel assembly. Update the VPD
information in the new operator panel.
2. I/O board (See notes 4 on page 27.)
If the problem is fixed, go to "MAP 410:
Repair Checkout" in the RS/6000 and
Eserver pSeries Diagnostics Information for
Multiple Bus Systems. If the problem persists,
go to "MAP 1540: Minimum Configuration" on
page 50 to isolate the problem.
A device may be set to use the same SCSI bus
ID as the control adapter. Note the ID being used
by the controller/adapter (this can be checked
and/or changed via an SMS utility), and verify
that no device attached to the controller is set to
use that ID.
If settings do not appear to be in conflict:
1. Replace the SCSI cable.
2. Replace the device.
3. Replace the SCSI adapter (or I/O board if
connected to one of the two integrated SCSI
controllers on the I/O board). (See note 4 on
page 27.
Note: In a "twin-tailed" configuration where there
is more than one initiator device (normally
another system) attached to the SCSI bus, it may
be necessary to change the ID of the SCSI
controller or adapter with the System
Management Services.