
3-3
Catalyst 3550 Switch Hardware Installation Guide
OL-6155-01
Chapter 3 Troubleshooting
Diagnosing Problems
Table 3-1 describes some common problems and their solutions.
Table 3-1 Common Problems and Solutions
Problem Solution
System LED is not on, and the
switch does not run POST.
• Check that the power cable is connected to the switch and to a
known power source.
• Test the power cable on another switch.
• Connect a working power cable from another switch.
System LED is amber.
• An internal fan fault is detected. Either check the switch itself,
or use the show env user EXEC command to check for a failed
fan.
• The switch might be overheating. Use the show env user EXEC
command to check for an overtemperature condition. If there is
an overtemperature condition:
–
Place the switch in an environment that meets the
environmental requirements given in Appendix A,
“Technical Specifications.”
–
Make sure that the fan intake and exhaust areas are clear.
• A fatal POST error is detected. See the “Understanding POST
Results” section on page 3-1.