IBM x3800 - System - 8865, Manual

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Universal Serial Bus (USB) port problems
v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v
See Chapter 3, “Parts listing, System x3800 Type 8865,” on page 107 to determine which components are
customer replaceable units (CRU) and which components are field replaceable units (FRU).
v If an action step is preceded by “(Trained service technician only),” that step must be performed only by a
trained service technician.
Symptom Action
A USB device does not work.
1. Run USB diagnostics (see “Running the diagnostic programs” on page 71).
2. Make sure that:
v The correct USB device driver is installed.
v
The operating system supports USB devices.
v A standard PS/2 keyboard or mouse is not connected to the server. If it is, a
USB keyboard or mouse will not work during POST.
3. Make sure that the USB configuration options are set correctly in the
Configuration/Setup Utility program menu (see the User’s Guide for more
information).
4. If you are using a USB hub, disconnect the USB device from the hub and
connect it directly to the server.
Video problems
See “Monitor problems” on page 55.
Light path diagnostics
Light path diagnostics is a system of LEDs on various external and internal
components of the server. When an error occurs, LEDs are lit throughout the
server. By viewing the LEDs in a particular order, you can often identify the source
of the error.
The server is designed so that LEDs remain lit when the server is connected to an
ac power source but is not turned on, provided that the power supply is operating
correctly. This feature helps you to isolate the problem when the operating system
is shut down.
Any memory, microprocessor, or VRM LED can be lit again without ac power after
you remove the microprocessor tray so that you can isolate a problem. After ac
power has been removed from the server, power remains available to these LEDs
for up to 24 hours.
To view the memory, microprocessor, or VRM LEDs, press and hold the light path
diagnostics button on the memory card or on the microprocessor board briefly to
light the error LEDs.
The LEDs that were lit while the server was running will be lit again while the button
is pressed.
Many errors are first indicated by a lit information LED or system-error LED on the
operator information panel on the front of the server. If one or both of these LEDs
are lit, one or more LEDs elsewhere in the server might also be lit and can direct
you to the source of the error.
Chapter 2. Diagnostics
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