Replacing a faulty Switch Dock USB port requires technical skill—proceed with caution (voids warranty). First, buy a replacement USB port kit (includes USB port, soldering iron, and tools) from Amazon or electronics stores. Unplug the dock and remove the four screws on the bottom using a Phillips screwdriver. Pry open the dock’s case with a plastic pry tool—start at the edges and work your way around. Locate the USB port module on the dock’s circuit board. Use a soldering iron to heat the solder joints connecting the old USB port to the board—carefully remove the old port. Clean the solder pads with a desoldering braid. Position the new USB port on the board and solder it in place—ensure the pins are aligned correctly. Reassemble the dock and test the USB port by connecting a controller. If you’re not comfortable soldering, contact Nintendo Support for repair—official repairs are safer for beginners.