While your TV's HDMI input doesn't actually turn on or off, it isn't active until you connect a device and switch to the right input channel. With a few minutes of setup, you'll be ready to enjoy media from your computer, phone and tablet on a bigger screen.
Connecting HDMI to Your TV
Connect one of the connector ends of your HDMI cable to your device's HDMI-out port, then connect the other end to your TV's HDMI-in port. Some devices like smartphones and tablets use a different HDMI-out connector type, such as Type-C or Mini-HDMI, or Type-D or Micro-HDMI. Make sure you have the correct cable before you get started, or you won't be able to make a connection between your device and your TV.
Switching Input Channels
Turn on your device and your TV. On your remote, press the Input button and cycle through the input channels. If you don't have a remote handy, the Input or Channel Up and Channel Down buttons on your TV should also work. Wait a few seconds on each channel before moving to the next, so that your device's display has enough time to load on your TV screen. Once you see your device's display on the TV, you're on the right channel and ready to go.
If you aren't getting any picture or sound from your connected device, check to make sure the cable connection is secure. Check the cable for broken, split or frayed sections and check the connectors to make sure there isn't any damage. If you still don't have any picture, the problem may be that your device, cable or TV is equipped with HDCP copyright protection, while one or two of the other devices aren't HDCP-compliant. If this isn't the case, your cable, the HDMI-out port on your device or the HDMI-in port on your TV may not be working properly.