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New Member

clueless CCNA student needing help with 3550 switch

The company I work for has given me a broken cisco 3550 switch to play with. I tries to boot however when booting in the hyperterminal it is outputting dashes. The cisco guy at work says it may just need a new flash card. The network admin says it may just need a firmware upgrade or the IOS is corrupt. Could you please give me some pointers so that I dont have to go into this without any advice. I have been studying for my exam for some time now and know how to move around in a switch or router but have never ran into any problems that I could solve just yet. This switch is a 3550 with 32 ports. The cisco tech has also said all I need to do is open it up and take out the flash. I have not started working on this project but do have soem ideas like holding down the mode button while booting it up. I am not sure how to upgrade the firmware if it will not even boot up. Thanks in advance.


Re: clueless CCNA student needing help with 3550 switch

Are you seeing any junk characters while booting or no characters at all?

In the first case, you can try changing the baud rates of the hyperterminal session


New Member

Re: clueless CCNA student needing help with 3550 switch

I am getting the following:

bu ? ? ?

? ? ? ? ? ? ?

? ? ?

? ?

? ?


It is slighlty different after cutting and pasting it. Also the system and RPS led lights are amber. Baudrate? I will do some research on that. I am going in for the first time in a long time since school to the hyperterminal and an choosing com1. Not sure if that I remember what settings to change for this.

New Member

Re: clueless CCNA student needing help with 3550 switch

I reconfigured the config.txt file by holding the mode button in during startup. This seemed to work. I renamed the config.txt file to config.old and during the new configuration I am getting this error:

!!! WARNING: The switch is not usable !!!


Error with Switch Core BIST test.Returns: Test Complete Low : 0x00000011, Test C

omplete High : 0x000000FF

I am logged in now with the new configuration and it is letting me do whatever. The Cisco guy at work is telling me this is the error that he thinks the flash memory is creating.

Could you help me out thanks

New Member

Re: clueless CCNA student needing help with 3550 switch


Amber light means POST test is failing.

To know which test in POST is failing, issue the command:

'show POST'