If the controller you are using has not been paired with a receiver, you can use one of the following methods to pair both devices.
Press the MENU button on the controller, then navigate to WIRELESS>FIND RECV to scan for active receivers and automatically pair. The LED on the controller will turn green once paired.
Press the MENU button on the MDR.S, then navigate to WIRELESS>CHANNEL and select the same channel number as the controller to begin pairing. The LED on both the controller and receiver will turn green once paired.