What part is the black box next to the steering column

I have a 2000 vw jetta, and the trunk will not open I have only a valet key. The switch just blinks when I try to open it. There is a black box with 2 wire harness plugged into it that makes a clicking sound but I cant figure out what part it is. When I unplug the harness the interior lights dont work. Can this be bad or blown?