IBM 365X/XD (2625) Clock Radio User Manual


 
The advanced diagnostic tests are intended to test
only
IBM products. Non-IBM products or modified options can
give false errors and invalid responses.
Hard Disk Drive Replacement Strategy:
Always try to run a low-level format before replacing a hard
disk drive.
Attention
The drive startup sequence in the computer you are
servicing might have been changed. Be extremely
careful during write operations such as copying,
saving, or formatting. Data or programs can be
overwritten if you select an incorrect drive.
How to Use Error Messages
Use the error codes displayed on the screen to diagnose
failures. If more than one error code is displayed, begin
the diagnosis with the first error code. The cause of the
first error code can result in false error codes being
displayed. If no error code is displayed, see if the error
symptom is listed in the Symptom-to-FRU Index for the
computer you are servicing.
How to Read POST Error Messages
POST error messages are displayed on the screen as
three, four, five, or eight digits. The error messages that
can be displayed as shorter POST messages are
highlighted in this index. Some digits will represent
different information for SCSI errors versus non-SCSI
errors.
The following example shows which digits display the
shorter POST error messages and also defines the SCSI
information in an eight-digit error message.
Shorter POST Messages
┌────┬────┬────┬────┐
┌────┬────┬────┬────┬────┬────┬────┬────┐
│ │ │ │ │ │ │ │
└────┴────┴────┴────┴────┴────┴────┴────┘
Reserved ││││││Size (SCSI)
└────┴────┘ Slot Number (SCSI)
Device Code Logical Unit Number (SCSI)
ID (SCSI)
All SCSI devices are set to a different SCSI ID.
Duplicate SCSI ID settings can generate a false error
message. Use the SCSI ID to determine whether the error
message is coming from an internal or an external device.
Introduction
7