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Core issue

Module problems occur when either the system status LEDs indicates a problem, the modules are not recognized or show faulty, or when users experience poor performance. The LED status on each switching module indicates whether the switching module has been initialized correctly. The Supervisor Engine must be operating properly before the switching module initializes. If a switching module is improperly installed in the switch, it does not function.


To resolve this issue, perform these steps:

  1. Capture the command output of the show version and show module commands.   
  2. Determine if the software version you are running supports this module. If an upgrade is required, always check the Catalyst Family Release Notes first and choose the version you need to upgrade to.   
  3. Consult the Catalyst OS (CatOS) hardware configuration portion of the Software Advisor.   
  4. Determine if the status is faulty for that module.   
  5. Determine if the show test command shows that this module passed all its diagnostic tests (as of the last bootup on the switch). Note any F results.
  6. Determine if the status shows disable, as this indicates that the module was administratively disabled. In this case, the status LED is orange.   
  7. Issue the set module enable <mod> command.   
  8. Have a console session open and capture the bootup Power-On Self Test (POST) diagnostics and any system error messages.   
  9. Reset the module by issuing the reset <mod> command. Issue the hw-module slot reset command to restart an individual module in Cisco IOS -based Catalyst switches.   
  10. Determine if the output of the show test 0 command shows that this module passed all of its diagnostic tests on bootup.   
  11. Remove the module and inspect it for bent pins.   
  12. Reseat the module, firmly press down the ejector levers and tighten the captive installation screws.   
  13. If the output of the show module command shows that the status is still faulty, try the module in another slot.   
  14. Slot 2 accepts line cards or a Supervisor Engine. If necessary, power off or on the switch.   
  15. If the status is still faulty, the module has failed. Remove and replace the module.  

    Note: In some cases, a badly seated card can cause symptoms that appear to be a hardware failure. A badly seated card can cause traffic corruption on the backplane, resulting in various problems occurring in the Catalyst chassis.  

    For example, if one module corrupts traffic on the Catalyst backplane, this can cause the self test to fail for both itself and other modules. Reseating all the cards can resolve this issue and allow the self tests to pass. For the switch to operate properly, all modules must fully engage the chassis backplane.  

If the issue is not resolved, please contact Cisco Technical Support online using the TAC Service Request Tool.

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