3Com 1000, User Manual

Page: 125 / 152

C
T
R O U B L E
-
S H O O T I N G
The following is a list of problems you may see
when managing the Switch with suggested courses
of corrective action to take. If you have a problem
which is not listed here and you cannot solve it,
please contact your local technical support represen-
tative.
LEDs
Power LED does not light:
Check that the power cable is firmly connected to
the device and to the supply outlet.
Check the unit fuse. For information on changing
the fuse, refer to
“Power Supply and Fuse” in
Appendix A .
On powering-up, the MGMT LED lights yellow:
The unit has failed its Power On Self Test (POST) and
you should contact your supplier for advice.
On powering-up, the MGMT LED flashes yel-
low:
The installed Plug-in Module has failed its Power
On Self Test (POST). Try re-installing the Plug-in
Module, ensuring it is properly seated. If the prob-
lem persists, contact your supplier for advice.
The Plug-in Module Status LED lights yellow:
If the MGMT LED is flashing yellow, the Module
has failed its Power On Self Test; refer to the previ-
ous advice. Otherwise, the Module’s agent software
is not installed correctly. Refer to the User Guide
supplied with the Module.
The Plug-in Module Status LED flashes yellow:
The Module is not recognized. You may need to
download a version of the Switch’s management
agent software that recognizes the Module (refer to
“Upgrading Software” on page 4-29 ), or remove
the Module. Contact your supplier for further
advice.
A link is connected and yet the Status LED does
not light:
Check that:
■
All connections are secure
■
Fiber cables are free from damage
■
The devices at both ends of the link are
powered-up
■
The connection uses cross-over cable if you are
linking a 10BASE-T or 100BASE-TX port with a
device which is MDIX-only