Airmatic Malfunction when towing and mushy ride always
Thread Starter
Member
Joined: Feb 2019
Posts: 146
Likes: 43
2013 GL 450, 2020 GLE 350
Airmatic Malfunction when towing and mushy ride always
Just picked up a nice 2013 GL 450 with 90K miles.
I have had a few instances now of the Airmatic Malfunction message on the dash. It seems to only appear when I am towing (even a small trailer) or have some weight in the back.
When it happens, the rear shocks lose all pressure and sit low. After 1-2 more trips the system starts to work normally again and the error goes away.
When there is no error, the height stays fine. I can raise and lower without issue. It does though, in my opinion, feel like a bit too "mushy" when driving.
Hoping someone has some troubleshooting tips to help narrow down if this is the distribution block, wheel level sensors, air bags, relay, or ???
I've changed the airbags before on other MBs, but the symptoms there is that the car would lose height after sitting. This issue is different. Ride height can be fine, I hook up the trailer, and it seems to go down after I start driving.
I have had a few instances now of the Airmatic Malfunction message on the dash. It seems to only appear when I am towing (even a small trailer) or have some weight in the back.
When it happens, the rear shocks lose all pressure and sit low. After 1-2 more trips the system starts to work normally again and the error goes away.
When there is no error, the height stays fine. I can raise and lower without issue. It does though, in my opinion, feel like a bit too "mushy" when driving.
Hoping someone has some troubleshooting tips to help narrow down if this is the distribution block, wheel level sensors, air bags, relay, or ???
I've changed the airbags before on other MBs, but the symptoms there is that the car would lose height after sitting. This issue is different. Ride height can be fine, I hook up the trailer, and it seems to go down after I start driving.
Super Member
Joined: Jul 2019
Posts: 733
Likes: 297
From: New Orleans
2014 GL450, 1992 W140 300SD, 1993 W140 300SE, 1987 E30 Convertible
That is a basic physics question - more weight on back of vehicle - more force - more pressure to compensate for vehicle suspension height. Your compressor can't buildup enough pressure to lift your loaded car to the necessary height.
Thread Starter
Member
Joined: Feb 2019
Posts: 146
Likes: 43
2013 GL 450, 2020 GLE 350
I understand physics, but that would not explain why the back end would have lost pressure. If the compressor was weak it may not be able to add additional air - but it would not release the air in the system. Also, if the compressor were indeed weak, it would not raise the vehicle normally. It would take longer than specified. This is not the case.
Thread Starter
Member
Joined: Feb 2019
Posts: 146
Likes: 43
2013 GL 450, 2020 GLE 350
I was able to get my C6 working and performed the tests in Xentry. It appears to be a leak between the compressor and valve block. I am picking up a valve block on Monday and will try that first. Will likely replace the compressor too even if the block fixes it as I’m sure the excess running wore the compressor down.
