What does the following error signify each time the Mercedes S500 is started; “car is low, stop, visit workshop”? The Mercedes air suspension turns on each time the car is started.

This could be a case of an air leak in the suspension system which is causing the car to rise but is taking too long to reach normal driving level. Here the shock absorbers should be examined and listened to for air leaks. The air-hose connected above each shock should be checked as well. It is preferable to have this checked by a mechanic since they will be able to differentiate and diagnose.