IBM 6648 - Manual (Page 40)

General checkout
This general checkout procedure is for type 6568/6569/6648/6649 computers.
Attention:
The drives in the computer you are servicing might have been
rearranged or the drive startup sequence 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.
Diagnostic error messages appear when a test program finds a problem with a
hardware option. For the test programs to properly determine if a test Passed,
Failed or Aborted, the test programs check the error-return code at test
completion. See “IBM PC Enhanced Diagnostics” on page 35.
General error messages appear if a problem or conflict is found by an
application program, the operating system, or both. For an explanation of
these messages, refer to the information supplied with that software package.
Notes:
1.
Type 6568/6569/6648/6649 computers default to come up quiet (no beep
and no memory count and checkpoint code display) when no errors are
detected by POST.
To enable beep and memory count and checkpoint code display when a
successful POST occurs, do the following:
a.
Select Start Options in the Configuration/Setup Utility program (see
“Setup Utility program” on page 41).
b. Set Power-On Self-Test to Enhanced.
2. Before replacing any FRUs, ensure that the latest level of BIOS is installed
on the system. A down-level BIOS might cause false errors and
unnecessary replacement of the system board. For more information on
how to determine and obtain the latest level BIOS, see “BIOS levels” on
page 49.
3. If multiple error codes are displayed, diagnose the first error code
displayed.
4. If the computer hangs with a POST error, go to “Symptom-to-FRU index”
on page 69.
5. If the computer hangs and no error is displayed, go to “Undetermined
problems” on page 90.
6. If an installed device is not recognized by the diagnostics program, that
device might be defective.
26
Hardware Maintenance Manual: IBM NetVista Computer Types 6058, 6059, 6269, 6568, 6569, 6578, 6579, 6648,
6649