i had that problem, all it was my "wire thing" dont know what its called, was hooked to the door card proply, he might of had the door card off to change speakers or the window regulator or sumit, and didnt know what he was doing and didnt clip it back on!
it would be a case of gettin the door card off which i doubt you will be able to do cause theres screws at the bottom.......
il have a look later and see cause its raiining quite bad now