The transmitter and headphone in HT4186 set is LOCKED to each other, they should auto reconnect once both devices are powered on.
1. Power the transmitter with the giving USB cable connecting with any valid USB power source. Switch on the transmitter, you will see LED flashed BLUE.
2. Power on the headphone by pressing and holding the power button until LED on the headphones turns on and showing flashing BLUE.
3. Put them next to each other and wait for 5-10 sec, they will auto-connect. You will see SOLID BLUE light both on transmitter and headphone and hear "Your device is connected" from headphone.
4.If still not connected, give the A button a click, or give the power button on the headphones a click, both actions will help the set to actively seeking each other, and try to establish a connection. Put them next to each other , wait for both light to turn solid BLUE.