If a monitor connected to your Type-C Multimedia Adapter shows no signal, try these steps:

• Use a direct HDMI to HDMI cable on the HDMI port, or a direct Mini DisplayPort to DisplayPort cable on the Mini DisplayPort port. Adapters and converter cables are not supported.
• Go to System Settings > Displays and click Detect Displays (hold the Option key on Mac).
• Connect the monitor directly to your computer, without the adapter, to confirm the monitor works.
• Disconnect and reconnect the adapter.
• Confirm your computer’s USB-C port supports DisplayPort Alt Mode, which is required for video. Not all USB-C ports carry video.

If the problem continues after these steps, submit a support request.