Enable the system setting
On the Switch, open System Settings and find Pro Controller Wired Communication under Controllers and Sensors. Enable it before testing the docked USB connection. In Gtuner IV, the Switch guide specifies USB Automatic or USB Nintendo Switch as the output protocol. An explicit selection can help if you are switching the same adapter between consoles.
Use the docked setup as the first test where possible. An undocked connection through a USB-C OTG adapter is a different physical arrangement. Check the documented requirements for the console and adapter you actually own before assuming that instructions for a dock apply unchanged.
Check input and output as separate links
Connect a compatible controller to the Titan Two and a data-capable micro-USB cable from OUTPUT to a USB port on the dock. The Switch documentation describes the original Pro Controller protocol without an authentication controller requirement. Leave any additional profiles inactive and try menu navigation or the system’s controller input test.
If Gtuner IV sees the preferred controller but the Switch does not respond, inspect the dock connection and the output protocol. If the controller is missing from Device Monitor as well, start with the front input port and controller cable before changing Switch settings again.
Add wireless only after the wired test
The setup guide documents Bluetooth output as its own procedure using the optional Titan Bluetooth module, a configured microSD card and an appropriate source of power. Follow that pairing procedure for wireless output rather than applying instructions intended for a controller that is connected wirelessly on the input side.
Sources
Titan Two AI publishes these guides independently. ConsoleTuner makes the Titan Two device and Gtuner IV.