I was wondering if there is anyone that can help me...my 2002 CL 500 has a message on the dash---ACTIVE BODY CONTROL....drive carefully....The car is lower on the driver's side....I was at the street light and the car just dropped lower on its own and then smoke started coming from the front wheel on the driver's side......Can someone tell me what may be wrong??? right now the car's air suspension is not working and the car is looking lop-sided and leaning lower on the driver's side, where the front tire is exactly right above the fender...

 

Hi,
I think you have diagnosed this yourself.
ABC requires the air suspension system to be operational. In simple terms the ABC limits the extent the car rolls in a bend. To do this it temporarily jacks the appropriate corner of the vehicle.
Your air suspension has collapsed on one corner. This is why you have smoke from that corner. The wide tyres are rubbing due to the suspension being fully down. The handbook warns of this condition and this is why you have the dash warning. The extent of the rubbing can render the tire unusable and presents a safety hazard.
The question is therefore why one corner/side is down. A dealer will be able to access the suspension control ECU which will have codes which will help in diagnosis. However, since the ther 3 corners are up the main air supply system must be working. It is therefore likely to be either a leak in the air line going to the effected corner, the air distribution valve (I think this is located forward of the RF wheel behind the plastic wheelarch panelling, the height sensor on the faulty wheel (adjacent to top suspension member under wheel arch or the airmatic strut itself. Struts are pretty reliable after the initial settling in period so would suggest the height sensor (after checking for leaks).
Check the condition of the pins on the electrical connector to the appropriate height sensor. Has there been water ingress? Blue deposit on pins.
Hope this helps.
Don't know how handy you are so can't make an indication as to whether it is just best to take the car to the dealer. The fault code should tell you how bad the problem is. A MB dealer will charge for reading the code and you should get a printed output with all the car details. Suggest you don't change the strut unless fault code points directly to it.
It is also just possible, but unlikely, that the fault is in the connection of the height sensor to the ECU. Unplugging and replugging this connector could resolve. Not sure where the ECU is but guess it will be in one of the black boxes under the hood near the firewall.
It is extremely unlikely that it is the ECU.

 

the oil leaks.

ABC control unit recognize sudden level change and lock the valves...deactivates the ABC.

this is safety function to avoid blowing up the front tires on high speed and save your dear life.

find the leak, fix it, and delete the fault to re-activate ABC.