I have a 2006 s500. I consistently see other members and their threads on the failures behind this system. But on the other hand, I do see many that are satisfied and happy. I bought a 2006 because I have much confidence in that many of the kinks have been worked out by the last year of production on the W220.

My questions are?
-How do you know if your airmatic is working normally?
-What are warning signs?
-What are the proper steps the car should take when the ignition is turned off, on, or when a door is open?
-Are there any test I can do to check to see if the airmatic is functioning properly?

I would appreciate your help guys!!!
Thanks
Joe

 

Airmatic is working normally when the car maintains its proper height (including rising to compensate for a passenger getting in, and a release of pressure if one gets out, while the engine is running); when the airmatic pump runs quietly; when you hear the airmatic pump only for a short while after starting, or while the suspension is very active. When you press the "raise" button on the dash, the front should rise approximately 3/4 inch, and lower when you press it again.

Warning signs are 1) Cracks forming in the mastic at the top of the front struts, indicating that a seal beneath the mastic may be leaking (this can be repaired with a new top seal kit, about $550 parts & labor for both sides). See post #15 at https://mbworld.org/forums/s-class-w...ic-failed.html for a good example of what this looks like. Post #18 in the string shows the seal without the mastic; the mastic is not the seal itself - it is a vibration damper for the brass valve neck shown in post 18. 2) Your car appearing lower than normal when parked on level ground; it can be low in front, in the rear, or on one strut. 3) The airmatic pump running a lot when the car has not been parked for a long time, or when it has not been driven on rough pavement or with a lot of stop-and-go. 4) A noisy airmatic pump. 5) When you notice the car rise noticeably after it has been shut down for only a short time (the airmatic may lose some pressure when it is parked overnight, or for several days, and you may see it rise, then seemingly lower - that is common; no pneumatic system maintains a perfect seal. What is actually happening is the front struts rise, and then the rear struts do - the hood ornament may seem to move up, then down. All that is happening is the car is leveling).

The car may release air with a slight, sharp noise soon after the engine is shut down (it sounds almost like a drop of water hitting a hot exhaust pipe). This is normal. The release may happen a few seconds after shutdown, and that may occur as you open the door to exit; it's a coincidence. Opening the door does not cause the release.

A bad airmatic relay can cause the pump not to come on when it is supposed to, and the car will gradually lower over time, and not rise when the engine is started. Even worse, it can cause the pump to run excessively, resulting in frequent releases of the overpressure, and burning the pump out. Since '04 or '05, cars with airmatic are equipped with a relay by Hella, which has fewer failures than the older Siemens relay did. The Hella relay and the part number are shown in the link above. They are available at auto parts stores for about half what the dealer charges.

The best thing you can do to check for warning is to note what normal operation looks and sounds like (you're probably just fine now), and note deviations. Check for cracks in the front strut mastic periodically. I note the movement of the "star" on the hood against marks on my garage wall, every so often, to see how much the car is rising after it has been parked for several days. Of course, if you get dashboard indications of problems, follow your owner's manual and have the problem diagnosed and repaired. Don't be fooled by the fact that the problem may be intermittent, and the warning light goes out for a while - get it fixed!

Here is some good shorthand on symptoms and causes of problems: Post #6 at http://www.benzworld.org/forums/w220...yes-again.html - except it should also note that the front struts can fail at locations other than the top seal, and there is no "repair" of the strut for such failures.

 

Thanks for such a complete write-up. You answered a lot of questions that I have been too afraid to ask. I wont obcess next time I start the car after a week or so and see it rising.

 

I replaced the right front air matic strut, it brought the front back up but the message appeared.
AIR MATIC VISIT SHOP why did this message appear everything looks normal do I need to have the computer reset or is there something else wrong please advise.

 

What did you replace it with? An Arnott unit, OEM or something else?

 

when I put the key in and turn it, I get the message NOT RECONNISED this happened after the battrey went flat. and idea's anyone

 

Warren if you have few minutes could you please write a few steps manual for air suspension investigation for leaks after suspension replacement.
As it looks like some people had the same issue like me and after replacement of front air struts still experiencing faults!
So how would you check if you have this problem like me?
The soap and water is done and no leaks on the tops!
But the strut was replaced and the car drops the side overnight to the tyres.
After start it levels back to normal and stays normal for driving or even parking for hours.
Only after about 10 hours drops down and loses its height only on that side where it was replaced.
Where is the valve block located? And how to go through on the whole system?
As by eye I cant see anything wrong at this point...
I will hook the car up on a Star Diagnostic tool on the weekend but I really want to do this myself once and for all I want to know all about this system!
Thanks,
Peter

 

I quoted you just to show you my last comment on this thread as I meant to send it to you!
Thanks in advance Warren and please only when you have time!
I think it would be useful for some of us!

 

This is some excellent info, I'm actually going to check out a S500 and the info I gathered from this post is gold.
Thanks Warren!

 

Peter, I am not a tech; and writing what you suggest would be something more appropriate for a tech. You can find the answer to some of your questions, such as the location of the valve block, in the W220 S-Class Encyclopedia at http://www.benzworld.org/forums/w220...tart-here.html

I tried to maintaing the Encyclopedia on this forum as well - but I could not "lock" the thread to keep extraneous discussions out - and the discussion questions made it unusable as a reference tool, so I stopped. I can lock the thread on BW, so I maintain it over there.

I realize that analyzing a question may take a good bit of reading. Often, you must go to a lot of links to get a full answer. However, the Encyclopedia is a compilation of the efforts of many good people; my work only brings their efforts together. The true knowledge is contributed by a LOT of people. Unfortunately, there is no way I have the time to "stitch" it all together.

 

Thanks so much for all the great info. I hope I'm not asking a silly or repeat question but if I have problem #4 (A noisy airmatic pump) as cited above, does that mean the pump and/or entire system needs to be replaced, and any idea what the cost might be?

 

Pump if is broken u can get original off German eBay for about 220 euros.
Plug and play under right wheel arch.
Some say you can replace some parts inside pump if noisy... but have no experience with it.

 

Definitely the entire system does not need to be replaced

They sell a replacement piston seal for the pump as well as rubber mounts . These are usually the cause of a noisy pump and will fix it right up for about $30