Funny sound while hand washing car.
Thread Starter
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
Likes: 28
From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
Funny sound while hand washing car.
I washed my car Sun and noticed an intermittant sound every 5 or 10 seconds while I was washing the front wheels. Almost like an electric motor engaging and disengaging. The car was off and had been overnight but I was wondering if this was the brake drying function?? It came from the front end close to the wheels and I only noticed it while I was rinsing the front end and the wheels?
Last edited by C300Sport; Oct 21, 2008 at 04:52 PM.
Senior Member
Joined: Sep 2007
Posts: 366
Likes: 1
2008 C300 SPORT (white)
I washed my car Sun and noticed an intermittant sounds every 5 or 10 seconds while I was washing the front wheels. Almost like an electric motor engaging and disengaging. The car was off and had been overnight but I was wondering if this was the brake drying function?? It came from the front end close to the wheels and I only noticed it while I was rinsing the front end and the wheels?
i have heard it several times myself, thought it might be the TPMS??? dont no, I can ask next time im at dealer
MBWorld Fanatic!
Joined: Sep 2007
Posts: 1,258
Likes: 19
From: Mississauga, ON CA
15 Mercedes C400, 12 Mercedes C250 coupe
i also know about this sound, same goes for a friend's C63.
I believe its some kind of FAN (possible for the Command) it runs for a while even after the car is off and key is out
I believe its some kind of FAN (possible for the Command) it runs for a while even after the car is off and key is out
MBWorld Fanatic!
Joined: Jun 2008
Posts: 2,073
Likes: 85
From: San Francisco, CA
2017 E300
thats so weird. it cant be the brake drying feature cause thats when the brakes are actually being used.
but thats interesting you mention this, because i was sitting in my car (off) and i noticed that just wen you pull the key out, the command center continues to hum for a while. weird.
but thats interesting you mention this, because i was sitting in my car (off) and i noticed that just wen you pull the key out, the command center continues to hum for a while. weird.
MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Noises. I hear noises..
I washed my car Sun and noticed an intermittent sound every 5 or 10 seconds while I was washing the front wheels. Almost like an electric motor engaging and disengaging. The car was off and had been overnight but I was wondering if this was the brake drying function?? It came from the front end close to the wheels and I only noticed it while I was rinsing the front end and the wheels?
What about your cell phone? Mine beeps loudly when I come in range(or leave it) when walking near the car in the house. Even when the car is off.
MBWorld Fanatic!
Joined: Feb 2004
Posts: 5,143
Likes: 1
From: South Orange County, CA
4 wheels
My W203 did the same thing. It's the AC system, probably refrigerant flowing slowly from the high side to the low pressure side. Entirely normal.
What about your cell phone? Mine beeps loudly when I come in range(or leave it) when walking near the car in the house. Even when the car is off.
What about your cell phone? Mine beeps loudly when I come in range(or leave it) when walking near the car in the house. Even when the car is off.
Trending Topics
MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Refrigerant on the move
It's R134A.
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
MBWorld Fanatic!
Joined: Feb 2004
Posts: 5,143
Likes: 1
From: South Orange County, CA
4 wheels
yea yeah its R134A. it could be the pump since on the e63 there was always this noise and the dealer isolated it to the AIP so thats why I mention that.
wakka wakka
Thread Starter
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
Likes: 28
From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
Last edited by C300Sport; Oct 22, 2008 at 05:46 PM.
Member
Joined: Mar 2008
Posts: 197
Likes: 1
2008 C300
C300..you are not crazy. I heard the same thing about 3 weeks ago. It is NOT anything to do with a fan for COMAND. I was leaving the house at 5:45 AM and opened the garage door. I passed the car (which had been sitting parked inside the garage) and put something in my mailbox and on the way back I heard what can only be described as a cross between a short squeal and a hiss coming from the car. I was like, "WTF?". I bent down closer to the hood and heard the noise again about 30 seconds later. This time I determined that it was coming from BEHIND the brake rotor on the left front wheel. I put my head close to the wheel and the car made the noise again about 30 seconds after that. I have NO IDEA what it was...but got in and drove to work. I stopped by the dealer on the way home, but they couldn't find anything wrong with the car. The tires still had all the proper air...and nothing has become of it since. Each day when I go out to my car, I listen for the noise...but it has never happened since.
Thread Starter
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
Likes: 28
From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
lol...yeah there is a lot more humming, whirring and buzzing in the C Class than any other car I have owned, but so far most are identifiable and are the result of good technology...hopefully this is just another one of those. 
Newbie
Joined: Dec 2008
Posts: 1
Likes: 0
2008 E350 4MATIC
Same issue on an E350
Same as Hazemonster describes. Even when the car has been cool for some time I hear the same hissing/beep coming from the left front side of the engine compartment. It persists for about 30 seconds with a few seconds between each hiss/beep, sometimes cycles multiple times. I thought at first it was coming from behind the left front tire, but when I pop the hood and remove the engine cover it seems to be coming from somewhere closer to the block. I also took it to the MB dealer and they could not reproduce.
MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Squeeee
Same as Hazemonster describes. Even when the car has been cool for some time I hear the same hissing/beep coming from the left front side of the engine compartment. It persists for about 30 seconds with a few seconds between each hiss/beep, sometimes cycles multiple times. I thought at first it was coming from behind the left front tire, but when I pop the hood and remove the engine cover it seems to be coming from somewhere closer to the block. I also took it to the MB dealer and they could not reproduce.
It's refrigerant expanding through the system and can be heard randomly even a day after shutdown. It is entirely normal.
Super Member
Joined: Nov 2008
Posts: 604
Likes: 29
From: SA
2008 C350-Sport-AMG-Active Agility Pack(Not reliable) +Izuzu KB6 3L(It seems Reliable)+Mazda
I was told it is a function to keep the air circulating after you left the car, for your benefit when you return, not cooling other eqpt..It's explained somewhere in the manual apparently.
Last edited by Moto_Guzzi; Dec 7, 2008 at 11:20 AM.
MBWorld Fanatic!
Joined: Dec 2006
Posts: 6,498
Likes: 335
From: Europe
223.168 & 213.012 & 906.633 & 214.005
But where did you get the idea that the W204 compressor was electric motor driven? All I've seen have been belt driven. Anyway, even an electric motor driven AC would have pressure stored in that can take quite a while to even out.
Thread Starter
MBWorld Fanatic!
Joined: Oct 2008
Posts: 2,601
Likes: 28
From: Atlanta, GA
2008 C300 Sport 6 Speed Manual, 1953 Chevy Bel-Air, 2015 Audi allroad, 1963 Chevy Apache
That is a feature on some MBs but it's not available on the C Class...at least not in the States. I am sure the S Class has it but not sure about other models.
MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
ELECTRIC
I almost always talk about freon when I know it is R134 or something similar, and those I talk to understand it is R134.
But where did you get the idea that the W204 compressor was electric motor driven? All I've seen have been belt driven. Anyway, even an electric motor driven AC would have pressure stored in that can take quite a while to even out.
But where did you get the idea that the W204 compressor was electric motor driven? All I've seen have been belt driven. Anyway, even an electric motor driven AC would have pressure stored in that can take quite a while to even out.
MBWorld Fanatic!
Joined: Feb 2004
Posts: 3,986
Likes: 6
From: SEATTLE WASHINGTON USA
'08 C300 Lux Barolo Red Beige Leather P2 MM 18" wheels '84 944
Rest
I used this all the time in my C320, winter and summer, and miss it nearly as much as mirror tiltdown.
So, since we don't have it, it's not in the manual.
