IBM 2256 Computer Hardware User Manual


 
Chapter 1. General Checkout
This general checkout procedure is for Types 2254, 2256, 2257, 6336, 6337, 6339,
6341, 6342, 6346, 6347, and 6348 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
Diagnostics on page 12.
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:
v Types 2254, 2256, 2257, 6336, 6337, 6339, 6341, 6342, 6346, 6347, and 6348 computers
default to come up quiet (no beep and no memory count and checkpoint code display)
when no errors are detected by POST.
v To enable beep and memory count and checkpoint code display when a successful POST
occurs, do the following:
1. Select Start Options in the Configuration/Setup Utility program (see Setup Utility
program on page 10).
2. Set Power-On Self-Test to Enhanced.
v 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 199.
v If multiple error codes are displayed, diagnose the first error code displayed.
v If the computer hangs with a POST error, go to Symptom-to-FRU Index on page 69.
v If the computer hangs and no error is displayed, go to Undetermined problems on
page 109.
v If an installed device is not recognized by the diagnostics program, that device might be
defective.
001
1. Power-off the computer and all external devices.
2. Check all cables and power cords.
3. Make sure the system board is seated properly.
4. Set all display controls to the middle position.
5. Power-on all external devices.
6. Power-on the computer.
7. Check for the following response:
v Readable instructions or the Main Menu.
© Copyright IBM Corp. 2000 1