Help needed. freelander 1 (53plate). TD4

[xyz05]

Hi, thank you for looking.
My TC and hill decent light are constantly on. I plugged in a trailer light board and it's been like that since. As a result, I have no reverse lights and no brake lights. I've changed the foot brake switch and had the diagnosis machine reset the truck. TC light and hill decent light came back on. If there is someone who can help, I will be very grateful. Regards.