Lenovo System x3750 M4 Installation And Service Manual page 35

Note: The system service label on the underside of the cover also provides information about the location of
the light path diagnostics LEDs.
To access the light path diagnostics LEDs, press the blue release button on the operator information panel
and pull forward on the unit until the hinge of the operator panel is free of the server chassis; then, pull down
on the unit so that you can view the light path diagnostics LEDs.
Light path
diagnostic
LEDs
Operator information
panel
The following illustration shows the LEDs and controls on the light path diagnostics panel.
Light Path Diagnostics
• Boot code display: This display provides boot error codes that indicate the point at which the system
stopped during the boot block and the power-on self-test (POST). A boot code is a byte value that
is produced by UEFI. In addition to UEFI codes, this display provides error codes in the event of a
microprocessor error or a power fault. Along with the IMM2 event log, the error codes can provide
suggested components to be replaced.
• Remind button: This button places the system-error LED on the operator information panel into the
Remind mode. In Remind mode, the system-error LED flashes once every 2 seconds until the problem is
corrected, the server is restarted, or a new problem occurs.By placing the system-error LED indicator in
the Remind mode, you acknowledge that you are aware of the last failure but will not take immediate
action to correct the problem.
• Reset button: Press this button to reset the server and run the POST. You might have to use a pen or the
end of a straightened paper clip to press the button. The Reset button is in the lower-right corner of the
light path diagnostics panel.
Release
button
.
Chapter 1 The Lenovo System x3750 M4 Type 8753 server
21