seeing that you're a subscriber and you have access to all the PDF's... i'd look at the wiring diagram and find what color wire goes to the door indicator... i'd assume when it opens, it completes a circuit hence why you hear the beeping noise.. i believe if you ground out the indicator completely and take it out of the loop, you would no longer hear the buzzing noise.. however your interior lights would also not come on when you open the door doing it this way...
i cant think of any other way to do it...