In some environments the nice blinking LEDs on our controller based access points are not welcome: in some hospital environments they are said to create panic related reaction with some patients, in some school they are said to attract too much attention... well, you may be asked to make sure that this AP LEDs are disabled.
This is a controller CLI command. To disable the LEDs for an AP called AP5 (check your AP names with show ap summary):
(Cisco Controller) >config ap led-state disable AP5
To disable LEDs on all APs:
(Cisco Controller) >config ap led-state disable all.
Nice and easy. As you can guess, use the config ap led-state enable to revert the command.