user244075

In my '96 E320 behind the sunroof switch and interior lights I hear a loud buzzing, like what you hear from a supermarket parking lot lights at night. I know it isn't the light bulbs because I took them out, besides why should they buzz. I know the sunroof motor is also located behind the lights. Can anyone tell me if I now need to replace the motor? The sunroof opens and closes fine. Thanks.

jadi

Same here with my 97 E420. Started last week. Were you able to find out what the problem is? Anybody's input will be greatly appreciated. Thanks.

sosh

I could be mistaken but I recall that there is a temp sensor for the HVAC system in that area with a mini fan to pull the air into it. Could be that

LorinserLV2

LOL


I thought i was the only guy with that issue.


Lately i havent heard that buzz, but about 2 or 3 months ago, everytime i started the car there was that thing, and it remained about 15 or 20 min then stopped, and some other times it started and stopped right after....

pokerFACE

we've always had it in our 97. My dad in all these years has never noticed so we never got it fixed. Drives me nuts though.

Is there a microphone up there (presumably for ambient noise processing for the audio?)

ed-E300TD

I recently developed this same problem. Only thing I've done recently is change the battery. Lights seem to work fine, but the noise is definitely coming from that area.

Any new insights since this question was last posted?

Thanks,
Ed

Fabio D

I think is the A/C temp sensor (with a little motor integrated) you ca hear the sound exactly in the little grille?

The black surroud grille in the rearview mirror is a microphone for the Integrated phone (comes too in a prewired cel phone cars).. but the other little grill integrated in the lamp is the inside temp sensor for the A/C..

Fabio Daniel

ed-E300TD

When I cover that black circular grill with my hand, the noise level remains the same.

If the noise is coming from there, should I still be able to hear it when it's covered?

Could the noise be coming from the light fixture, or a bulb?

Fabio D

The black circular grille in the mirror is the MIC for the Cel Phone (buzzing sound is not here)., You need to cover with the hand the other little grille integrated in the lamp unit (in this place have the little motor with the TEMP sensor for the AC)

Or you can unmount the lamp assembly to see were the buzzing comes

Fabio Daniel

mbenz420

And i thought i was going crazy too...same exact noise in my 97 E420 =/..i try to tune it out but its just a constant noise

ohlord

replace the CC ambient air intake fan unit.
Diy somewhere here and abouts.

Fabio D

1+

ed-E300TD

Fabio - you nailed the location. The noise is coming from a grate just to the right of the sunroof actuator.

Oh Lord - no luck finding a DIY link. Searched the W210 forums.

Any further advice on a fix?

Thanks,
Ed

Fabio D

Yep! is the interior air temp for the A/C, you need to replace the little fan. remove the entire lamp & you will see the little motor (i'm pretty sure is sold separatly)

Fabio Daniel

A.T.C.

Does anyone have a solution with a part # for this problem?