W202 Buzzing sound from behind interior light

[tosborne]

I wondered if any one had noticed a slight buzzing sound behind the interior lamp on the W202?

I asked at the dealership today and there is in fact, a small fan behind the lamp which drags air over a temperature sensor. The fan runs when the key is in the "2" position.

Mine was making a droning noise (you can notice it if you switch the fan off with the ignition on), cost of a replacement, £47!

 

[Simon]

I’m amazed to hear there’s a little fan up there! What year is your car?

For your information I’ve had a listen to mine and it’s quiet.

Just turn the radio up a bit

 

[jimmy]

I have heard about this fan before but have not noticed mine making a noise.

Test it with a small piece of tissue paper, it should stick to the grill if there is a fan in there.

 

[Shude]

It's the climate control "sniffer". I unplugged mine once while messing with the plugs on the back of the dome light and climate control went crazy, it thought the temperature was -35 degrees or something so it decided to blow HOT!

 

[tosborne]

It's a 1999 model C240. I think this part only exists if there is climate control in the vehicle - either the electronic or manual version (which mine is!)

 

[GrahamC230K]

Originally posted by tosborne
It's a 1999 model C240. I think this part only exists if there is climate control in the vehicle - either the electronic or manual version (which mine is!)

If you have the manual controls, then it is just aircon, not climate control.

 

[Will]

I have noticed this on my 1996 C200 Esprit Manual.
It has no air-conditioning or climate control. As far as I am aware, it is just a standard heater. When I first bought the car I noticed it, and then I forgot about it and it seemed to go away. Then a few weeks ago it occurred again - normally when you first get into the car.
What would this fan/sensor be for if I dont have air-con or climate? and why (apart from obviously being a good high central point) would the put a temperature sensor next to a light bulb???
Cheers
Will

 

[smiff]

Buzzing Sound.

I know this one well!
It is the interior temperature sensor, and I have one on mine even though it is non A/C.
It's the bearings in the tiny fan that sucks air in to sense temperature.
Sorry - no idea how to replace it, but I know I had to wait weeks for one to be delivered from Germany, and still pay £17 for the privilege.