I just picked up a new S550 and was wondering if anyone else is noticing the same thing I am??

When I turn on the AC, and the radio is off, i hear a constant electrical buzzing noise. The best way for me to describe the noise is that it sounds similar to when a computer is copying a floppy disc. It's weird. I notice it more when the fan speed is on 1, which is the lowest setting. Anyone else notice it on their S550?? It drives me nuts!

Thanks.

 

FWIW, just because the radio is off, doesn't mean the entire Command system is off and all the speakers are completely deactivated. There are still components of the Command system that remain on all of the time when the ignition is on.

I had a similar issue with my 745Li. It turns out it was the seat cooler fan. I got the car during the summer and I used my heat/cool seats a lot. I only noticed the faint sound when the radio was off and the A/C was low. Make sure your heat/cool seats are off.

If that's not it, move your cell phone as far away from your car as possible. Sometimes cell phones interfere with sensitive electronics and cause strange sounds. It happens all the time at my office. Whenever my phone is sitting next to one of my multi-line office phones, the office phone makes some strange sounds just before and after a call. When I picked up the bluetooth puck for my GL, I was directed to call the 800 number and check to see if my phone would work ok in the car. The guy wanted a number off the back of my phone because even some Motorola Razr phones don't work properly in MB vehicles.

If that's not it. I might also suggest that you pull out all of the DVDs in your system including the nav DVD and see if the sound goes away. Maybe you have a slightly warped disc that is rubbing and the car is so quiet that you can hear it.

If that's not it, maybe something is going on with your bluetooth puck. Remove it and see if the sound goes away.

If that's not it..... you're screwed!

 

that sounds like an iterferance issue, considering this is a new model car im sure there will be a solution soon.

 

Robert,

Thank you for the suggestion regarding the cell phone as I always keep it in the cupholder right under the COMAND system. I will give that a try. If that doesnt work, I will try your other suggestions. Thanks so much!

Ryan

 

I dont own a MB so this could be way off from what is the problem but that noise and ac sounds like the a/c clutch. Just an idea and hope you get it resolved

 

Just drove the car without my cell phone in the cupholder-- noise is still there. Sounds like an electrical zapping sound. Weird things is, noise only comes on when I turn on the A/C and ONLY on the lowest fan speed. Tried fan speed on 2nd setting and noise is not there. Hmmmm

 

Defective blower unit?

 

I had the same thing on a 1994 500 SL, when the AC was set to the lowest possible level. It turned out to be a defective fan.

 

My wife's '05 S500 has been in the shop for the past 2 weeks. Replaced the evaporator unit, replaced the whole Command unit (cds would not play), replaced the cd changer (cds skipped) + whatever else they found wrong with it. Hopefully this is not a sign of things to come on your 1st year S550!?!

 

Robert-

Sorry to hear. Hope they get the car back to your wife soon!

I have about 1100 miles on the car now. Everything has been perfect except for the zapping noise. I am going to make a service appt tomorrow. I looked up to see if there were any open recalls on the car and there arent any (yet), so hopefully it wont have take 2 weeks to fix!

 

I had the same problem with my E500 in 2003 and now again with my S550.I have been told it's the valve's knocking in the engine.It's very subtle but can be very annoying.The weird thing is my CL55 and E55 did not make this noise.Believe me MB knows about it.

 

A valve knocking in the engine? How does that cause a zapping noise in the dash on only with the AC on? But i guess anything is possible with all the high tech stuff on these new cars.

Faxon, have you brought in your S550 to the dealer yet? If so, what did they say?

 

Aero,
is the Bluetooth standard on the S?