v The server is restarted.
v A new error occurs, causing the system-error LED to be lit again.
The following table describes the LEDs on the light path diagnostics panel and
suggested actions to correct the detected problems.
Note: Check the system-event log and the IMM event log for additional information
before you replace a FRU.
LED
Problem
None, but
An error has occurred and cannot be
the
diagnosed, or the IMM has failed. The
system-
error is not represented by a light path
error LED
diagnostics LED.
is lit.
BRD
An error has occurred on the system
board.
CNFG
A hardware configuration error has
occurred. (This LED is used with the
MEM and CPU LEDs.)
Action
Use the Setup utility to check the system-event log for
information about the error.
1. Check the LEDs on the system board to identify the
component that is causing the error. The BRD LED can be
lit for the following conditions:
v Battery
v Missing PCI riser-card assembly
v Failed voltage regulator
2. Check the system-event log for information about the error.
3. Replace any failed or missing replaceable components,
such as the battery (see «Removing the battery» on page
229 for more information) or PCI riser-card assembly (see
«Removing a PCI riser-card assembly» on page 188 for
more information).
4. If a voltage regulator has failed, replace the system board.
1. If the CNFG LED and the CPU LED are lit, complete the
following steps:
a. Check the microprocessors that were just installed to
make sure that they are compatible with each other
(see «Installing a microprocessor and heat sink» on
page 240 for additional information about
microprocessor requirements).
b. (Trained service technician only) Replace the
incompatible microprocessor.
c. Check the system-error logs for information about the
error. Replace any components that are identified in the
error log.
2. If the CNFG LED and the MEM LED are lit, complete the
following steps:
a. Check the system-event log in the Setup utility or IMM
error messages. Follow steps indicated in «POST error
codes» on page 28 and «Integrated management
module error messages» on page 114.
65
Chapter 3. Diagnostics
Light path diagnostics
The following illustration shows the remind button and the LEDs on the light path
diagnostics panel. The light path diagnostics panel is inside the server under the
left-side cover, and the error LEDs are also visible through the left-side cover.
CPU VRMS_ERR
MEMORY
DASD/
RAID
NMI
SP BUS
FAN
POWER
SUPPLY
PCI
BUS
2
1
CONFIG
TEMP
REMIND
SEE INSIDE COVERFOR MORE SERVICE INFORMATION
Press the remind button on the light path diagnostics panel to acknowledge that an
error has occurred but indicate that you will not take immediate action. When you
press the remind button, the system-error LED flashes every 2 seconds until the
error is corrected. If another error occurs, the system-error LED stops flashing and
is lit again.
For more information about light path diagnostics, see the Problem Determination
and Service Guide on the IBM System x Documentation CD.
Diagnosing problems using light path diagnostics
LEDs in three locations on the server are available to help you diagnose problems
that might occur during installation. Use them in the following order:
1. LEDs on the front of the server: Look at the front of the server. If a system
error has occurred, the system-error LED on the front of the server is lit.
2. LEDs on the left-side cover: There are 13 LEDs and a system service label
on the left-side cover. Note the lit LEDs and follow the instructions on the
system service label.
3. LEDs on the system board: To identify the component that is causing the
error, note the lit LED next to the component.
90 IBM System x3500 Type 7977: Installation Guide
Chapter 3. Diagnostics
13
Identifying problems using status LEDs
If the System Error light in the operator information panel on the front of the server is
on, one or more LEDs inside the server may be on. Use the light path diagnostics to
identify the type of error that occurred.
For LED locations see “System board LEDs” on page 41.
Light Path Diagnostics
You can use the Light Path Diagnostics built into your server to quickly identify the
type of system error that occurred. The Light Path Diagnostics panel is located on the
system board just behind PCI adapter slot 1. When you press on the Light Path
Diagnostics button the LED on the top right corner of the panel will illuminate. This
shows that the diagnostic circuitry is working correctly.
Your server is designed so that any LEDs that are illuminated can be re-illuminated
without AC power after you remove the cover. This feature helps you isolate the
problem if an error causes the server to shut down. See Table 3 on page 14.
Important:
You have up to 12 hours to use the Light Path Diagnostic LED’s after AC
power has been removed from the server. After 12 hours you must power the server
up again to be able to use the Light Path Diagnostic LEDs to help locate system errors.
Table 2. SCSI messages.
SCSI Messages
Description
All
One or more of the following might be causing the problem.
•
A failing SCSI device (adapter, drive, controller)
•
An improper SCSI configuration
•
Duplicate SCSI IDs in the same SCSI chain
•
An improperly installed SCSI terminator
•
A defective SCSI terminator
•
An improperly installed cable
•
A defective cable
Action:
Verify that:
•
The external SCSI devices are turned on. External SCSI devices must
be turned on before the server.
•
The cables for all external SCSI devices are connected correctly.
•
The last device in each SCSI chain is terminated properly.
•
The SCSI devices are configured correctly.
If the above items are correct, run the diagnostic programs to obtain
additional information about the failing device. If the error remains or
recurs, call for service.