Cisco Aironet 340 Series

Cisco Aironet Base Station: Correcting a Yellow Flashing LED

Document ID: 5807

Updated: Dec 13, 2005



This document discusses a Base Station flashing yellow LED and explains how to fix the problem.



There are no specific requirements for this document.

Components Used

This document applies to all models of the Cisco Aironet 340 series Base Station, and applies to all software versions.

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.


Refer to Cisco Technical Tips Conventions for more information on document conventions.


After an initial power up of the Base Station, sometimes the middle LED continues to flash yellow. This is after the Base Station has been configured through the Base Station Client Utility (BSCU). This can indicate that the Base Station has not received the configuration across the wireless link from the client adapter.


Use this solution to solve the problem.

In order to start the BSCU, double-click the icon, or select BSCU from the Windows Start menu. Complete these steps:

  1. Select Client and click Edit Client Properties.

  2. Verify that the web encryption box is NOT checked.

  3. Select OK to finish.

  4. You can now associate with the Base Station, but the middle LED still flashes yellow.

  5. In order to start a Telnet session on your PC:

    1. Select Start

    2. Select Run

    3. Type the telnet command.

    4. Press ENTER.

    5. When the Telnet connects to the Base Station, a screen with this information appears:

      Cisco BSM340 V8.48 Main Menu BSM340_37652a
      Option Value Description
      1 - SSID [ "tsunami" ] - SSID - Service set identification
      2 - EncryptionKey - WEP encryption key in ASCII
      3 - HexKey - WEP encryption key in hex
      4 - Configure - Use new SSID and key
      5 - Mode [ Access Point ] - Operating mode
      6 - Name [ "BSM340_37652a" ] - Base station name
      7 - DHCP [ on ] - Obtain network address automatically
      8 - History - Log and alarm history
      9 - Close - Close the telnet session
      IP Address : Mask:
      DNS servers:,
      Domain Name:
      Enter an option number or name
  6. Type 1 to configure the SSID.

  7. Type the SSID you want. Make a note of this number, because you need this number later.

  8. Press ENTER.

  9. Type 3 to configure the WEP key.

  10. Type the WEP key you want. Make a note of this number, because you need this number later.

  11. Press ENTER.

  12. Repeat steps 9 through 11 as the Base Station prompts you to confirm the WEP key.

  13. Type 4 to activate the SSID and WEP key changes you have just made. The client loses association with the Base Station until the completion of steps.

  14. Return to your BSCU, select Client and Edit Client Properties.

  15. Select the web encryption check box.

  16. Enter the WEP key and SSID previously configured.

  17. Click OK when done.

    The Base Station middle LED is a steady green, and your client reassociates.

Related Information

Updated: Dec 13, 2005
Document ID: 5807