Hello!
I own a 2005 S211 om646, the back suspension is airmatic. I went to a service with a specific Mercedes tester, and only a level sensor was faulty. We changed the sensor. Before the sensor it lowered every night. After sensor change it only lowers when its cold or rarely when its parked down slope. When I turn the engine on it raises quickly and have no problems afterwards. Could it be the air bags? Thank you all very much.

 

Even after replacing the level sensor, if the suspension lowers overnight or under specific conditions, the air springs (air bags) themselves might have small leaks. These leaks can become more evident in cold weather due to the contraction of materials, or when parked on a slope, which might stress certain components differently. Additionally, the air lines or connections could have minor leaks or the valve block might not be sealing properly, allowing air to escape when the car is off. To further diagnose the issue, I recommend checking the fault codes from the Airmatic Control Unit. These modules can provide detailed information about any persistent or intermittent issues with the suspension system. Using a full system scanner like the youcanic will give you access to all relevant systems and potential error codes. If you're relying on a basic OBD2 scanner like the Bafx Products 34t5, it might not detect these specific suspension-related issues. Have you inspected the air springs and connections for any visible signs of wear or damage that might indicate a slow leak?

 

Hello, thank you for your response. Yes, we used a full system scanner, like a youcanic one, not a basic obd2 scanner. Also we've used the tester often yet it doesn't state any airmatic problem. After replacing the sensor it didn't lower at all, maybe only once in a month, but since it got cold, its lowering itself. Wondering if I should change the air springs or not.