Oracle Sun Server X4-4, Service Manual

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Troubleshooting With Diagnostic Tools
54 Sun Server X4-4 Service Manual • October 2015
Top Cover
The server top cover is an important component for a properly functioning server. The top
cover is vital to the server cooling subsystem because it helps to maintain the pressure areas
within the server. The top cover also protects against damage to internal components and
accidental exposure to hazardous voltages. For these reasons, the server top cover is interlocked
to the server power. The interlock is created by a switch. The switch has two components; one
component is mounted inside the server on the housing for power supply, PS1, and the other
component is mounted on the underside of the top cover. When the cover is installed on the
server, these two components align, the switch closes, and power flows to the server. When the
cover is removed, the switch opens, breaking the flow of power. If the cover is removed while
the server is powered on to full power mode, power to the server is immediately switched off.
Action
: If the server does not power on, check that switch is intact and properly aligned. Ensure
that the server top cover is in place and sits flat and snug on top of the server. Ensure that the
interlock switch components have not been damaged, removed, or misaligned.
Prevention
: After removing the top cover, take care that the cover doesn't get bent, or that
the component on the underside is not damaged. When servicing the server, take care that the
internally mounted interlock switch component doesn't get damaged or misaligned. Never
operate the server without the top cover installed.
Troubleshooting With Diagnostic Tools
The server and its accompanying software and firmware contain diagnostic tools and features
that can help you isolate component problems, monitor the status of a functioning system,
and exercise one or more subsystems to disclose more subtle or intermittent hardware-related
problems.