For wireless powerline extender, there is a LED also works as a button. It looks like the picture below.
If the button is pressed for 2 seconds, the LED will be in WPS procedure and blink slowly. It will be solid on for 300 seconds to indicate a successfully WPS connection.
If it is pressed for 5 seconds, wireless function can be disabled or enabled. It will blink quickly when wireless is enabled, otherwise it will be off.