Q: connecting to a 5ghz wi fi channel

Hey simmsfootball,

Thanks for the question. If I understand correctly, you want the iPhone 5s to connec to a 5Ghz network. I would recommend that you read these articles, they may be helpful in troubleshooting your issue.

iOS: Connecting to Wi-Fi - Apple Support

To connect to a network

 

1. Tap Settings > Wi-Fi.
2. When Wi-Fi is on, your device will automatically search for available Wi-Fi networks:
   
3. Tap the name of your desired Wi-Fi network.
4. When your device is connected to a Wi-Fi network, a checkmark will appear to the left of the network name. The Wi-Fi logo  will also appear in the status bar at the top left of your display:
   

iOS: Troubleshooting Wi-Fi networks and connections - Apple Support

iOS and OS X: Recommended settings for Wi-Fi routers and access points - Apple Support

Thanks for using Apple Support Communities.

Have a good one,

Mario