In case you need to physically locate and access point that is controlled by a WLC you can do so by making the LED status light blink on demand.
You will first need to enable debug mode on the AP to enable the controller to send commands to it from its CLI
debug ap enable your_access_point_name
NOTE:The output of these commands is sent only to the controller console, regardless of whether the commands were entered on the console or in a TELNET/SSH CLI session.
To make a specific access point to flash its LEDs for a specified number of seconds, enter this command:
debug ap command \"led flash seconds\" your_access_point_name
You can enter a value between 1 and 3600 seconds for the seconds parameter.
To disable LED flashing for a specific access point, enter this command:
debug ap command \"led flash disable\"Â your_access_point_name
You can disable debug mode once you\’ve located you AP by using this command or simply close your ssh session
debug ap disable your_access_point_name
[source:CISCO WLC Config Guide]
