Self level suspension fails to rise CLS Shooting Brake

[gio65_00]

Hi,

Hoping someone can help.

I have a 63 plate CLS Shooting Brake which is experiencing rear air suspension issues. I believe the suspension is self levelling but noticed past day or two, once the car has been switched on, the suspension no longer rises. I have had no message from the onboard computer so unsure what has caused the issue. Could it be electrical such as the fuses or relays? Or is it more technical such as the airbags or compressor?

I attach some pictures with this thread.

Any help is much appreciated.

 

[weds]

Usually if the car is this low there would be a 'car raising please wait' (or something similar) on the dash. Can you hear the compressor running under the rear bumper ? I wonder if the link arm for the level sensor has fallen off. Then the ECU wont know how high or low the car is but will adjust the suspension to compensate to wherever the link arm has gone too...

When my link arm came off it went to fully raised so there no reason whist yours couldn't go to fully down.

 

[ThinkPad]

Had the same with a CLS I bought recently. When parked this would happen. When starting, I did get the rising please wait message and had to wait before driving. The conclusion was that there was an issue with the air suspension - mechanical. I ended up returning the car as it had other problems too. I think the consensus was that this would need a fix which may involve replacement of rear air springs, which could be a four figure repair. Good luck with getting it inspected - probably best to visit a respected indie.

 

[gio65_00]

Usually if the car is this low there would be a 'car raising please wait' (or something similar) on the dash. Can you hear the compressor running under the rear bumper ? I wonder if the link arm for the level sensor has fallen off. Then the ECU wont know how high or low the car is but will adjust the suspension to compensate to wherever the link arm has gone too...

When my link arm came off it went to fully raised so there no reason whist yours couldn't go to fully down.

No messages at all on the dash, even when it was working, that the car is raising or something similar. Can’t hear the compressor running at all. I’ve got the car booked with an indie on Monday morning, hopefully it’s not a massively expensive job.

 

[gio65_00]

Had the same with a CLS I bought recently. When parked this would happen. When starting, I did get the rising please wait message and had to wait before driving. The conclusion was that there was an issue with the air suspension - mechanical. I ended up returning the car as it had other problems too. I think the consensus was that this would need a fix which may involve replacement of rear air springs, which could be a four figure repair. Good luck with getting it inspected - probably best to visit a respected indie.

Thanks mate, got it booked with an indie on Monday am. Hoping it’s not mechanical. To me it seems odd both have gone at the same time.

 

[weds]

No messages at all on the dash, even when it was working, that the car is raising or something similar. Can’t hear the compressor running at all. I’ve got the car booked with an indie on Monday morning, hopefully it’s not a massively expensive job.

Sound even more like the sensor link has come off. There plastic and prone to break (mine did) replaced with stainless steel ball joints. I thought you might be able to see them through the wheel but i've just had a look and you'll need to pop the wheel off to see them, there's one each side not sure if one is the suspension and the other the headlight leveling. but it was my drivers side link that came off..

That being said the air springs/air line etc are prone to leaking but they'll give an error message if the car is low. I've had both air springs replaced and air lines.

 

[gio65_00]

Sound even more like the sensor link has come off. There plastic and prone to break (mine did) replaced with stainless steel ball joints. I thought you might be able to see them through the wheel but i've just had a look and you'll need to pop the wheel off to see them, there's one each side not sure if one is the suspension and the other the headlight leveling. but it was my drivers side link that came off..

That being said the air springs/air line etc are prone to leaking but they'll give an error message if the car is low. I've had both air springs replaced and air lines.

I’ll see what the indie says but it sounds as if that is the case. Will report back on Monday and confirm. Any photos of what these sensor links look like? (Possibly a stock photo) Thanks

 

[alexanderfoti]

Sound even more like the sensor link has come off. There plastic and prone to break (mine did) replaced with stainless steel ball joints. I thought you might be able to see them through the wheel but i've just had a look and you'll need to pop the wheel off to see them, there's one each side not sure if one is the suspension and the other the headlight leveling. but it was my drivers side link that came off..

That being said the air springs/air line etc are prone to leaking but they'll give an error message if the car is low. I've had both air springs replaced and air lines.

Yes most likely, this is one of the only failures that won't trigger a dash warning, as the car does not know its low!

 

[gio65_00]

Yes most likely, this is one of the only failures that won't trigger a dash warning, as the car does not know its low!

Sounds promising. Hopefully the indie will also confirm the same. I’ll run this past him, indirectly and then take it from there. Thanks to all for your help. I’ll update post-Monday

 

[gio65_00]

Cars gone in, hopefully it’s nothing major! Car did not sound nice to drive at all this morning. Turn the steering wheel and heard the tyre scraping against the inner wall, car bouncing at the rear on every bump on the road!

 

[weds]

When my link arm broke the car went fully inflated, I drove it for a few miles but it was so uncomfortable and possibly doing damage I got it trailered home ( I still had about 20 miles to go)

 

[ajlsl600]

Yes most likely, this is one of the only failures that won't trigger a dash warning, as the car does not know its low!

All that tech. But it's still down to brain in seat to suss out wots goin on.. Think I rather just hav simple spring. Easy to see wots goin on. Even they break, however primary eye sight and minimum brain use works this out fairly rapidly.

 

[gio65_00]

Cars back and the cause was burnt wiring, new wiring has been put in and all good, suspension level back to how it should be. Not sure how the wire has burnt but I guess it’s one of those things. £50 so not too bad.

In terms of the self level air suspension, how does that work in general? All new to me.

 

[weds]

Thanks good news... It's quite simple, 2 air inflatable bags instead of springs, an air compressor to inflate them and a level sensor connected the suspension arm to adjust the height also an air solenoid to add or release air from the air bags. Put a heavy load in the back, car goes down, level sensor detects that and the compressor fires up and inflates the air bags back to the correct height. Take the load out the car raises the level sensor detects that and the solenoid opens releasing air so the car goes back to the correct height.. simples, until it isn't...

 

[ajlsl600]

Check wiring for source of issue. Might f something expensive up next time. Well done getting to issue, now get to cause

 

[malcolm E53 AMG]

Thanks good news... It's quite simple, 2 air inflatable bags instead of springs, an air compressor to inflate them and a level sensor connected the suspension arm to adjust the height also an air solenoid to add or release air from the air bags. Put a heavy load in the back, car goes down, level sensor detects that and the compressor fires up and inflates the air bags back to the correct height. Take the load out the car raises the level sensor detects that and the solenoid opens releasing air so the car goes back to the correct height.. simples, until it isn't...

Yep, steel springs break and air springs (bags) eventually leak all part of the joys of owning a car. I suppose the downside of airmatic cars is the suspension replacement costs that air ride doesn’t come cheap. MB front air struts come in at £1k+ a side and rear air springs £500 a side. Arnott tends to be the go-to aftermarket supplier at about 50% of those prices

 

[gio65_00]

Thanks good news... It's quite simple, 2 air inflatable bags instead of springs, an air compressor to inflate them and a level sensor connected the suspension arm to adjust the height also an air solenoid to add or release air from the air bags. Put a heavy load in the back, car goes down, level sensor detects that and the compressor fires up and inflates the air bags back to the correct height. Take the load out the car raises the level sensor detects that and the solenoid opens releasing air so the car goes back to the correct height.. simples, until it isn't...

Cheers @weds for this very simple explanation until it goes all wrong

 

[gio65_00]

Check wiring for source of issue. Might f something expensive up next time. Well done getting to issue, now get to cause

I’ve asked my indie for his view on the possible cause. Hopefully he’ll reply soon, as I don’t get many replies from him lol (busy man!)

 

[gio65_00]

Yep, steel springs break and air springs (bags) eventually leak al part of the joys of owning a car. I suppose the downside of airmatic cars is the suspension replacement costs that air ride doesn’t come cheap. MB front air struts come in at £1k+ a side and rear air springs £500 a side. Arnott tends to be the go-to aftermarket supplier at about 50% of those prices

That’s good to know. How often do they tend to go @malcolm210 ? I suppose it’s all about how you drive the vehicle and the state of the roads etc

 

[malcolm E53 AMG]

That’s good to know. How often do they tend to go @malcolm210 ? I suppose it’s all about how you drive the vehicle and the state of the roads etc

Airmatic struts and springs tend to fail due to age (rubberised components) front struts 15-20 years and rear air springs 10-15 years on average. If the airmatic system starts to fail due to a leak and looses air pressure regularly this then tends to make the the air pump work overtime and wear out due to overheating so any issues are better dealt with sooner than later