Buzzing/Humming from overhead courtesy light area

[Parx]

In the overhead area where the courtesy light switches are there is a perforated plastic area. In the last few days this has started to make a buzzing/humming sound (not very loud) after switching the ignition to the 1st position. This continues whilst driving and for approximately 2 minutes after the ignition is switched off, when it eventually cuts out. I believe this is some type of very low fan?

The noise is there whilst driving, but not really noticeable due to traffic noise etc. Does this occur on anyone else's electric B? I find it annoying as the car is quiet otherwise, and it's only become noticeable in the last few days.

 

[JeffRay]

Weird. Are you sure it is not the pedestrian warning hum that is normal but shuts off when at speed?

 

[Parx]

Yes, fairly sure it isn't the pedestrian warning noise because when the car is parked there is no noise audible outside as the car is stationary and off. The hum inside the cabin is still there though, until 2 minutes later when it cuts out.

After Googling I have read that an E-Class had a similar problem which was diagnosed as a noisy climate control sensor/fan. When I took my B-Class to the dealership, they stated that another electric B in their workshop made the same noise so asserted it was normal. Personally I remain unconvinced, hence wanted to check with other owners.

 

[JeffRay]

Not normal. You just experienced the "we don't see a lot of these" syndrome. Do your best Larry David impression and insist that they escalate and tell them you consulted multiple other B-Class owners and it ain't so.

 

[Parx]

Thanks Jeff, will do this.