High Pitched Break Pedal Noise?
 

I just took delivery of my E 320 a few hours ago - Silver/Charcoal/CD/E2/E5 Launch Package.

I have to say that I really like everything about the car so far. However I noticed that there is a VERY high pitched, yet faint noise whenever my foot is on the break. The instant the break is released, the noise stops. It's definitely not breakdust and is coming from inside the car. It seems to be an electronically generated-type tone much like a hearing test (high and faint beeeeeep). My passenger didn't notice it until after I pointed it out, but now it's obvious every time I break - and unfortunately now impossible to ignore . Any thoughts or similar experiences? I plan to discuss with my dealer on Monday.

I hope it's something that can be fixed - other that this issue - so far so good! Great car!

Thanks in advance,

Seelander

High pitched noise, I would go back to the dealer - Some noise from the outside when you open the door, step on the brake and stop at a stoplight (like a small drrrr) is ok which is the electronic brakes.. You could feel something but not hear anything.. I'd take the car back to the dealership.

Now that you mention it, I remember hearing it a couple of times. It is extremely faint. If there is any noise at all (windows down, radio, A/C) etc its not noticeable. (Probably something in the electronic braking thingy for lack of a better technical explanation.)

Let us know what your dealer says. I'm curious but I don't think I would bother with it unless its really not supposed to do that and there is a known fix.

High Pitch Noise
 

I have the E500 and mine makes the same VERY HIGH pitch sound when I first start the motor in the morning. The noise goes away after a few minutes when the rpm drops. After this, the sound is very faint like described here. My car does not make a difference if I step on the brakes or not. The sound is loud outside the car, meaning you do not have to have the windows rolled up and the radio off. This noise was not here when I first bought the car, it appeared after about 500 miles. What is this noise?

Thanks...

No noise with my 500.

Same noise
 

I noticed the same high pitched noise, but it is only audible from outside the car and seems to have no relation to the brakes. What is that noise? Any ideas?

i hear a noise when we unl;ock thr doors, we always use keylessgo, so it must be when you open it, i always thought it was the airmatic sus adjusting the level of the car

Brake Noise
 

I do also hear the brake noise - which to my ears is more of a low grumbling. The unidentified noise I hear is more of a high pitched whine.

I did hear that brake pedal thing for a bit, but the last couple of times I tried to listen for it I couldn't hear anything at all.

In any case if my car makes any annoying noises I will ask the dealer to take care of it. BTW the motor mounts are in and I'm getting that done next week so I expect the "Musical Mercedes Experience" to soon become a thing of the past.

BENZOID:

Congratulations on getting the break-in miles behind you. Now the fun can begin.

Exactly what did you experience to know you needed the motor mounts? What did you notice? What did you tell your dealer and how did he respond?

I am not sure if I have the problem.....I do drift to the right so I'll have to get that taken care of.

My wood wheel was not on straight (it really does bother you) but I had the dealership fix it before I left.

Ed

high pitched noise
 

has anyone figured out what this is? i have it too. if you turn off the radio and drive down a quiet street, when you step on the brake as you approach a stop sign, you can hear a very faint high pitched sound. it's like a squeak but it's an electronic sound.

it's very slight and i personally don't mind it too much but i listen for it now that i know about it. it drives my wife crazy though.

I have an appointment with the dealer to look at this and a couple other things on Thursday, I'll let you know what they say. The high pitched noise is still in the break pedal, however not 100% of the time any longer, which is a good sign. I have hearing like a dog's so it really is a problem to me when radio is off. I think that some folks here said that the noise went away after several weeks, I have 600 miles on the car so far.

high pitched sound
 

Seelander, did you get this resolved?

i usually don't hear it because the radio, a/c, windows, etc...are on or opened and so it drowns out the sound.

but yesterday, i tested this again on a quiet slow street with all of the windows closed, a/c off, radio off, sunroof closed, etc. the high pitched noise is definitely still there.

i'm guessing that it's just a function of the brakes so i probably won't take it in. but if you found out what it is, please let me know. thanks.

Rock.

Rock,

sorry for delay. Yes, I took it in last week and they had no idea what was causing it. At the time I had about 600 miles on the car and the noise was fading from when I first bought it, however still there and noticable. They tracked the sound to the upper break line at the master cylinder. They replaced the upper break line (and noted that they had to "manually bend to make it fit (??!) - however the sound was totally gone when I drove off the lot. That being said I still hear an occasional recurrance of the noise, but it is about 10% of what it used to be - and very rare after the fix. I then started to have issues with my Brake warning light come on, but it's stopped - maybe just a computer reset issue. If I had to do it over again, I would put 1000 miles on the car before getting any repair work done to fix the noise. It might have gone away on it's own as it was fading at 600mi. Whole thing has left me unsettled about my brakes now.

Seelander

I've noticed the noise and just passed 900 miles on our E500. From my experience, it is a normal break in period noise usually only occuring in the first 1000 or so miles with new brakes and before "heating up" the brakes from use.

High-Pitched Noise from Brakes
 

I will occasionally hear this high-pitched noise when I ease up on the brakes a few feet before making a complete stop (force of habit to make a soft stop). I also noticed that the noise is non-existent when I DO NOT ease up on the brakes. I have duplicated the phenomenon a number of times and attribute the noise to my foot action.

Otherwise, no noise ...

Edit: I have 2,500 miles on the car.

I do not hear the high-pitched noise, but there is growling when I just started to apply or release breaks. Sounds like a small hydraulic pump of some sort. I wish MB published a technical supplement to their manual to explain what gets activated at what time (e.g., I hear mechanical sounds from under the hood when I open driver's door, another set when I turn the key to ignition, then the break sound). That would save owners a visit to the shop, and MB some warranty service time.

rumble
 

the low growling (or rumble) sound is normal. it's just the brakes. it happens to me when i shut off the car, start the car, and maybe even at some stop lights.

i agree that they should have this in the manual (if it isn't there) and the sales people should alert all owners of it when they take delivery of the car.

Rock.

Agree it would be a useful document for technically-oriented consumers.

The mechanical event you hear under the hood when the driver's door is opened is the SBC system charging up. It uses the door-open event as the cue to prep the brakes for operation, bringing the hydraulics online presumably both for the brakes themselves as well as the feedback-simulator for the brake pedal.

brake noise- high pitched
 

The person who described it like a "hearing test" is exactly what i have noticed> I have approx 600miles on my car.
further? try it with the car off- foot on the brake i hear it

did anyone have it fixed or do we live with it.

OK- Thought i was going crazy when i re-read my post.
I went to my garage- didnt start the car-
depressed the brake pedal -
engine off and cool-key in pocket


the noise is there-
engine off-

high pitched- juts like the gentlemen said - similiar to a hearing test sound

I heard it
 

I turned off radio yesterday and I heard it -- just as Rock72 described

I called the dealer and schedule an appointment -- my appointment is on 2/28. I did not hear the squeak sound this morning but I will keep an eye on it. (I have around 500 miles on my car)

Otto

yup
 

that's the sound all right. sounds light a high pitched hearing test type of sound. it's very faint and you have to make sure you have the radio off and the a/c fan off.

i have around 800 miles on the car now and it's still there. i don't know if it's enough to schedule an appointment with the dealer but i figured i would ask about it the next time i'm out there.

it's annoying but usually i don't hear it because i have the radio on.

Rock.

high pitched
 

OK went to dealer - service manager took it for a ride-
told me its the new fly by wire break system-
personally i think the model is so new they really do not know.

Also- can any of u step on the brake with the key out of the igntition and hear a whirring noice and the damned high pitched sound?

I feel like a dog and the special whistle.....

fly by wire
 

mike,

do you serve in the air force? i was discharged from air force, "fly by wire" is a fancy word when i were there.

otto