ML Air Suspension Problems Need Help

That sounds familiar. Compressor failure is a common problem. Have you checked for any obvious air leaks? Listen around each air strut and the compressor when the system tries to pump up. Is the suspension pump running continuously, or does it cut out after a short while? What error codes are you getting? Knowing the codes will help narrow down the problem.

How did you find the air leaks? Did you just listen for them? I'll check the codes later. I'm not sure if the suspension pump is running continuously. Where is the compressor located in the ML?

I just listened for the leaks. You can also try spraying soapy water around the air lines and struts; bubbles will form if there's a leak. The compressor is usually located near the front wheel well, often behind the fender liner. Getting the error codes will be the biggest help. If the compressor is running constantly, it likely has a major leak or the compressor itself is failing. If it's cutting out, it could be a faulty relay, a blocked filter, or the compressor overheating. Given all the symptoms and the error messages, I think you should visit a workshop. Air suspension can be tricky.

It was a defective cable or plug connection of the component. The workshop did a quick check and fixed it for 95€.