E220 w211 estate rear self levelling suspension

[Jes]

Hi guys
New here
Have a problem with the rear self levelling suspension on a 53 e220 w211 estate which has only rear air suspension
O/s rear airbag on the stops n/s bag still up no pump running at all
Checked all fuses that I am aware of
changed relay
Changed rear level sensor
Changed rear airbag (which had one of the terminals disintegrated tried a brand new pump all to no avail
I’ve no hair left
Has anyone any realistic ideas
Thanks jes

 

[amazighman]

Valve block?

 

[AndrewOl]

Check to see you are getting 12v to the compressor and that the connector is in good condition. I had to put a zip tie around mine to get a reliable contact.

 

[Jes]

Valve block?

Thanks for the reply there’s no valve block as such just a three way distributor on the rear subframe
One feed in and a pipe to either airbag
Cheers

 

[Jes]

Check to see you are getting 12v to the compressor and that the connector is in good condition. I had to put a zip tie around mine to get a reliable contact.

Cheers for the reply
I’ll double check that tomorrow
I don’t think anything appears to be triggering the relay to the pump
Cheers I’ll check that though
Thanks

 

[MJJ]

The ideal diagnosis is to get the car on Star diagnostics and run the various suspension test routines - this should identify where the fault is. Very few of us have access to Star however.

I have recently rebuilt the compressor with a new piston ring on my '09 S211 - mine was riding too low (but evenly) at the rear. During my diagnosis, it became clear that the car self-protects the compressor very diligently (but probably too late) and as soon as it knows that the compressor is failing to build air pressure, it seems to disable it permanently. On my car, I only got a white (i.e. minor/info) 'Malfunction' warning with a symbol of the car and an up arrow after about 45 minutes driving - this reset every ignition cycle. Fault code 5505 (Recovery times during filling of air suspension strut is too long) registered and readable with my iCarSoft scanner.

I rebuilt the compressor (search for bagpipingandy on YouTube and eBay, £25 kit and 2 leisurely hours work), refitted it, cleared fault codes, and after about 45 minutes of driving - the car was back to normal height and behaviour.

My assumption is a leak causes the compressor to work overtime, until it wears out and the car self-protects. By this stage, the damage has been done to the compressor. In my case, I had a leaking airbag a year ago and replaced both, but the compressor must have worked hard prior to replacement.

I found this post from Steve @ Avantgarde very useful in explaining, and helping me diagnose.

Martin.

 

[Jes]

The ideal diagnosis is to get the car on Star diagnostics and run the various suspension test routines - this should identify where the fault is. Very few of us have access to Star however.

I have recently rebuilt the compressor with a new piston ring on my '09 S211 - mine was riding too low (but evenly) at the rear. During my diagnosis, it became clear that the car self-protects the compressor very diligently (but probably too late) and as soon as it knows that the compressor is failing to build air pressure, it seems to disable it permanently. On my car, I only got a white (i.e. minor/info) 'Malfunction' warning with a symbol of the car and an up arrow after about 45 minutes driving - this reset every ignition cycle. Fault code 5505 (Recovery times during filling of air suspension strut is too long) registered and readable with my iCarSoft scanner.

I rebuilt the compressor (search for bagpipingandy on YouTube and eBay, £25 kit and 2 leisurely hours work), refitted it, cleared fault codes, and after about 45 minutes of driving - the car was back to normal height and behaviour.

My assumption is a leak causes the compressor to work overtime, until it wears out and the car self-protects. By this stage, the damage has been done to the compressor. In my case, I had a leaking airbag a year ago and replaced both, but the compressor must have worked hard prior to replacement.

I found this post from Steve @ Avantgarde very useful in explaining, and helping me diagnose.

Martin.

Hi mjj
Thanks very much for the reply
The car has been on star a while ago and the only code in there was o/s level sensor which was a little puzzling as it only has rear air but I changed the rear level sensor anyway.
Apparantly the pump wouldn’t run through the diagnostic program so I fitted a replacement pump and was still the same.
So fitted rear o/s air bag which as it turned out had one of the pins burnt/eroded away so I was fist pumpingbut didn’t do a thing.
I can fire the pump from the relay but it only runs for a few seconds then it acts like its up to pressure and turns off
I’m thinking that maybe the burning out of the pin on the airbag has blown something else that controls the triggering of the pump maybe ?
I’m not aware if it runs any kind of control unit for the suspension system which could have blown maybe ?
Cheers jes

 

[mcsparrow98]

Did you get anywhere with this Jes? I am having issues with my E280. I had everything rear suspension wise replaced when both airbags exploded. New shocks, level sensor, airbags, compressor etc....Car worked fine for about a year and then i needed to replace the rear driver side airbag because it had become damaged. Put a new airbag on, and it was working, but it caused the "malfunction message" to come on the dash. So i have replaced this bag with another new one, but now it will only inflate when the car is jacked up. Under the cars weight it will not inflate. Passenger side no problem, driver side - nothing.

According to my mechanic air is "horsing" out of the lines and there are no signs of leaks, but thinking about things logically if it is able to inflate when the car is jacked up, but not under the cars weight, doesn't this suggest that perhaps there could be a leak in the line supplying this airbag?