System Troubleshooting and Diagnostics
5.3 Interpreting Power-On Self-Test and ROM-Based Diagnostic Failures
>>>T 40 1 4 0
This command tests the memory on four memory modules. Use it after
running memory tests individually or within a script. If test 40 fails with
subtestlog = 6, examine R5–R8 to determine how many errors have been
detected.
Additional Troubleshooting Suggestions
If more than one memory module is failing, the CPU module, or backplane, as
well as other MS690 modules may be the cause of failure.
Always check the seating of the module before replacing it. If the seating
appears to be improper, rerun the tests.
If you are rotating MS690 modules to verify that a particular memory module
is causing the failure, be aware that a module may fail in a different way when
in a different slot. Be sure that you map out both solid single-bit and multibit
ECC failures as shown in step 2 of acceptance testing (Section 4.4), since in
one slot a board may fail most frequently with multibit ECC failures, and in
another slot with single-bit ECC failures.
Be sure to put the modules back in their original positions when you are
finished.
If memory errors are found in the operating system error log, use the CPU
ROM-based diagnostics to verify if it is an MS690 problem or if it is related to
the CPU or backplane. Follow steps 1–3 of Section 4.4 and step 4 above to aid
in isolating the failure.
5.4 Testing DSSI Storage Devices
A DSSI storage device (ISE) may fail either during initial power-up or during
normal operation. In both cases, the failure is indicated by the lighting of the
red Fault indicator on the drive’s front panel.
If the drive is unable to execute the Power-On Self-Test (POST) successfully,
the red Fault indicator remains lit and the Run/Ready indicator does not come
on, or both indicators remain on.
POST is also used to handle two types of error conditions in the drive:
•
Controller errors
are caused by the hardware associated with the controller
function of the drive module. A controller error is fatal to the operation
of the drive, since the controller cannot establish a logical connection to
the host. The red Fault indicator lights. If this occurs, replace the drive
module.
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