Hi,
I took the car to a Toyota dealer earlier for a quick check and the usb socket is not charging a phone so it seems like its dead.
I got the USB socket out of the dashboard and all the wires are correctly connected to it and to the back of the head unit and the other wire that branches off to the dashboard all connected properly.
So I guess either there's a setting I can't find switched off or the head unit or the USB socket are damaged.