buzzing w202 roof

[alramone]

just got myself a 96 w202 and have a real strange buzzing noise coming from the roof where the rear view mirror is. does stop after a while but i have no idea what it is? anybody?

 

[Dieselman]

The fan for the interior temperature sensor.

 

[stevesey]

As DM says - mine buzzes a couple of times a year, a quick tap and it stops.

 

[Shude]

It's probably the temperature "sniffer" fan in the dome light. If it only buzzes when the dome lights dim then it's an interior bulb not correctly seated within the clips.

 

[alramone]

ah thought it might have been somthing to do with the heating. it does not stop when tapped so i guess i'll have to take it apart and see if i can replace it. thanks for your help

 

[reflexboy]

Mine does the same but stops when the car warms up. I only discovered the fan's tiny motor by being my inquisitive self and taking it to bits.