I pulled the front interior light out on my 87 300e w124 to change the lamp and found a strange hose attached to the left and side of it which exits out the vents on the facia next to the sliding light switch, i thought the vents were for some optional buzzer of some description. can anyone say what this hose and vent do, it`s too big for vaccum, at a guess i`d say it`s a blower to demist the interior mirror but no air seems to come out of it.