IBM H Series Installation And Service Manual page 38

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 (operator panel should display OK).
The SMS configuration list or Boot sequence
selection menu shows more SCSI devices
attached to a controller/adapter than are actually
attached.
You cannot load diagnostics.
You have a problem that does not prevent the
system from booting.
You suspect a cable problem.
You Cannot Find the Symptom in this Table
All other problems.
2-4
RS/6000 Enterprise Server Model H Series Installation and Service Guide
Action
Reseat the operator panel cable.
If problem not resolved, replace in order:
1. Operator Panel Control Assembly. Remove
the VPD module from the old Operator
Panel Control Assembly (connector U2) and
place in the new one.
2. I/O board (See notes on 2-1.)
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 notes on
2-1 if the I/O board is replaced.)
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.
Go to "MAP 1020: Problem Determination" on
page 2-5.
Go to the Fast Path MAP in the Diagnostic
Information for Multiple Bus Systems.
See the RS/6000 Adapters, Devices, and Cable
Information for Multiple Bus Systems.
Go to "MAP 1020: Problem Determination" on
page 2-5.