Does your airmatic compresser start every time you unlock the car?
#1
Junior Member
Thread Starter
Join Date: Dec 2003
Location: Hallandale Beach, FL
Posts: 64
Likes: 0
Received 0 Likes
on
0 Posts
C32 AMG
Does your airmatic compresser start every time you unlock the car?
Does your airmatic compresser start every time you unlock the car?
Mine does.
Sometimes I get a red screen that says reducing braking effect. I never hear anyone talking about it, so I am curious.
Thanks
Mine does.
Sometimes I get a red screen that says reducing braking effect. I never hear anyone talking about it, so I am curious.
Thanks
#2
Senior Member
Join Date: Oct 2004
Location: Hertfordshire, UK
Posts: 271
Likes: 0
Received 1 Like
on
1 Post
ML 320 CDI
I would think the noise you hear is the SBC system charging itself, not the airmatic.
If you are getting a red message saying reduced braking then something is wrong with the SBC system, get it to the dealers ASAP
If you are getting a red message saying reduced braking then something is wrong with the SBC system, get it to the dealers ASAP
#5
Junior Member
Thread Starter
Join Date: Dec 2003
Location: Hallandale Beach, FL
Posts: 64
Likes: 0
Received 0 Likes
on
0 Posts
C32 AMG
I also hear air release when I hit the brakes...
I've never had a problem, but I am scheduled for service on Dec 27th so I'll get it checked.
Thanks
I've never had a problem, but I am scheduled for service on Dec 27th so I'll get it checked.
Thanks
#6
Senior Member
Join Date: Jul 2004
Location: Southern California
Posts: 274
Likes: 0
Received 0 Likes
on
0 Posts
'03 E500
Interesting...
when I lock or unlock my car..i hear 2 noises..a pshhhhhhhhhh..and a grrrrrrrrrrrrr... I thought it was the sound of my airmatic thing kickin in and then the car adjusting the ride height prior to rolling out.
when I lock or unlock my car..i hear 2 noises..a pshhhhhhhhhh..and a grrrrrrrrrrrrr... I thought it was the sound of my airmatic thing kickin in and then the car adjusting the ride height prior to rolling out.
#7
MBWorld Fanatic!
Join Date: Mar 2004
Location: Ft. Lauderdale Area, USA
Posts: 5,017
Likes: 0
Received 15 Likes
on
15 Posts
2015 ML 350
Very good description of the sounds. I noticed the other day that as soon as I unlocked the doors & started to get in the first thing in the morning, the car let the air out of the airmatic and the car lowered itself (Pssssssss...). As I stepped on the brake pedal to start the car (keyless go) I heard the GRRRrrr of the SBC pump. So there you go.
Trending Topics
#8
Super Member
Join Date: May 2004
Location: USA
Posts: 755
Likes: 0
Received 2 Likes
on
2 Posts
LS7 powered Corvette
Originally Posted by Barry45RPM
Very good description of the sounds. I noticed the other day that as soon as I unlocked the doors & started to get in the first thing in the morning, the car let the air out of the airmatic and the car lowered itself (Pssssssss...). As I stepped on the brake pedal to start the car (keyless go) I heard the GRRRrrr of the SBC pump. So there you go.
#10
MBWorld Fanatic!
Join Date: Mar 2004
Location: Ft. Lauderdale Area, USA
Posts: 5,017
Likes: 0
Received 15 Likes
on
15 Posts
2015 ML 350
Originally Posted by aceman
unlock the car and it lowers itself - think its a german engineering design to make entering the car easier
Happy holidays!
Aceman
![thumbs](https://mbworld.org/forums/images/smilies/thumbsup.gif)
Happy holidays!
Aceman
#12
MBWorld Fanatic!
Join Date: Mar 2004
Location: Ft. Lauderdale Area, USA
Posts: 5,017
Likes: 0
Received 15 Likes
on
15 Posts
2015 ML 350
Originally Posted by DarkStar
...my seat does move back when I open the door....
#13
Out Of Control!!
Join Date: Jul 2003
Location: North Scottsdale, AZ
Posts: 15,903
Received 4,432 Likes
on
3,150 Posts
'71 Pinto
Originally Posted by Barry45RPM
How tall are you? I'm 6'2", I think I drive far enough back so that the car feels its good enough to get out, even though there is about 3 more inches of rearward travel available.
Re-sync (compliments of another forum member, posted a while back):
(1) Menu, key dependent must be off;
(2) Exit car with all windows and roof closed, lock the car;
(3) Wait a minute or so, open all windows and roof with the key;
(4) Close all windows and roof with key;
(5) Unlock and enter;
(6) Move the seat completely forward and back several times to reset memory;
(7) Menu, convenience, set steering & seat and key dependent;
Unfortunately because of so many complaints (IMO so many owners not knowing how to correctly setup and operate this feature) MBUSA removed the seat function from the easy entry/exit and only the steering wheel adjustment remains (CLS, 10/05 delivery).
#14
Senior Member
Join Date: Jul 2003
Location: Bay Area
Posts: 412
Likes: 0
Received 0 Likes
on
0 Posts
03 E55
Originally Posted by Barry45RPM
How tall are you? I'm 6'2", I think I drive far enough back so that the car feels its good enough to get out, even though there is about 3 more inches of rearward travel available.
#15
Almost a Member!
Join Date: Jul 2005
Location: Texas
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
'06 E350, appearance/entertainment/ sunroof/DVD NAV/brilliant silver (C744)/Ash leather
Sources of noise
As indicated, this noise is most likely to come from the Sensotronic Brake Control System, in some occasions from the DC Airmatic, and is indeed absolutely normal:
The SBC system is functional as soon as it is wakened by:
opening a door
operating the central locking system
depressing the brake pedal
turning the key to position 1
operating the parking brake
Activating SBC will:
charge the accumulator (MOST LIKELY SOURCE OF NOISE !!)
perform a Predrive Check
move the pads towards the rotors with ~60 bar pressure
erase the fault memory
The DC Airmatic wake-up occurs with any one of the following "inputs":
key in the ignition
open any doors
open trunk lid
activate parking brake
pressing the brakes
Wake-up causes the DC Airmatic system to monitor vehicle ride height and adjust as needed dependent on vehicle load changes:
if level is >30mm lower than normal (0mm +/-10) it will raise to normal level (if reservoir pressure >11 bar)
if level is >65mm lower than normal, it will be raised even with a reservoir pressure of <11 bar by the compressor (prerequisite battery voltage >12.5v) to -63mm (critical level) (POSSIBLE OTHER SOURCE OF NOISE !!)
if level is >10mm higher than normal, it will be lowered to normal
The SBC system is functional as soon as it is wakened by:
opening a door
operating the central locking system
depressing the brake pedal
turning the key to position 1
operating the parking brake
Activating SBC will:
charge the accumulator (MOST LIKELY SOURCE OF NOISE !!)
perform a Predrive Check
move the pads towards the rotors with ~60 bar pressure
erase the fault memory
The DC Airmatic wake-up occurs with any one of the following "inputs":
key in the ignition
open any doors
open trunk lid
activate parking brake
pressing the brakes
Wake-up causes the DC Airmatic system to monitor vehicle ride height and adjust as needed dependent on vehicle load changes:
if level is >30mm lower than normal (0mm +/-10) it will raise to normal level (if reservoir pressure >11 bar)
if level is >65mm lower than normal, it will be raised even with a reservoir pressure of <11 bar by the compressor (prerequisite battery voltage >12.5v) to -63mm (critical level) (POSSIBLE OTHER SOURCE OF NOISE !!)
if level is >10mm higher than normal, it will be lowered to normal