What is an ABC or Active Body Control System?
The ABC or Active Body Control System is a type of suspension meant to help control your vehicle’s movements to stabilize it through risky maneuvers like taking sharp turns or braking quickly and is sometimes recognized as the “Drive Carefully” light on your Mercedes dash. As you can imagine, it is a pretty important safety feature. If it fails, your entire suspension system fails, and you can no longer drive safely. That is why you need to be informed of the issues that may arise with the Active Body Control system employed before it turns into a problem that can’t be fixed. Let’s look at some of the common problems the system has, why they occur, and prevention.
Common Issues With the ABC System
There are a few things you may notice are happening to your Mercedes-Benz while driving that could be an indicator of ABC System Failure. Other things are much harder to look for, so pay extra careful attention to the things that you can.
“Drive Carefully” Light On
If your “Drive Carefully” warning light comes on, this may be a signal that the control system is failing. The color of the and consistency of the warning light is key. Blue or white light tends to be related to minor issues while the red light is more serious. If any of these lights come on and go off right away, again not a big deal, but if they come on frequently or stay on, serious, and you should not drive your vehicle until you can have it repaired.
Car Sags When Parked
This can be normal and is nothing to worry about. After a few weeks of driving, you will likely notice that your car is sitting a little lower. However, having this problem within a week or less means that your system could be having issues.
The vehicle is Making Whining Noises
If you notice any unusual whining or humming noises, your problem may be with the pulsation dampener in your ABC system. It could also be a lot of other things but in conjunction with any of the other warning signs, this is the most likely cause.
Underlying Causes of ABC System Failure
Hydraulic Fluid Leakage
This is quite a common issue. Several different parts make up the ABC system, so it possible for many places the hydraulic fluid could leak from. When that happens, you may notice that your car will be sagging closer to the ground. In certain instances, this can make your car difficult to drive. The body of your vehicle may drag on the ground, damaging unrelated components to the failing system.
Improperly Sealed Valves
If the valves in the parts of your ABC system are not properly sealed and locked, the hydraulic fluid could leak from them. Note, you may not be able to see the leak or leaking hydraulic fluid. This is where a certified mechanic can help.
Debris Accumulation
The valve block can sometimes get dirty from road debris and if not cleaned and maintained in a while the filter will fail and need to be replaced.
How to Prevent ABC System Failure
The best prevention is following your Mercedes-Benz factory scheduled maintenance by a certified mechanic who can ensure the components are inspected and maintained correctly.
Fifth Gear Automotive Can Help
It may be difficult to find a mechanic other than at a dealership that will be qualified to handle either the maintenance or repair of the ABC System. Fifth Gear can help, we work on most all makes and models and specialize in Mercedes and other European makes. Contact us today to schedule an appointment our technicians are trained and certified to handle most any repair, regardless of the vehicle’s manufacturer, we have you covered.
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Fifth Gear Automotive
We are a family-owned independent automotive repair shop. We have over 100 years of experience with all domestic and import makes and models, specializing in European auto repair. Proudly serving for over 15 years Lewisville, Highland Village, Flower Mound, Lantana, Double Oak and the surrounding communities. We have one goal; Complete Customer Satisfaction on all your auto repairs.
ABC SYSTEM PROBLEMS MERCEDES W215 CL500 YEAR 2004 (CHASIS Nº WDBPJ75X4A042681)
My name is Pablo Valperga I am from Tucuman Argentina
I would like to ask a question about my Mercedes, when I bought it it had low blood pressure.
1st – I changed the tandem pump for a reconditioned one from the US, that’s where it all started, by not solving and not knowing the oil I used, I began to find out about the ABC system
2nd – I bought a second LUK brand pump in Germany, it started with 180 bar and then the pressure dropped to 75 bar.
3rd – I replaced the four shock absorbers “oring and seals” that I brought from Germany, according to the seller they were better than the original ones and nothing kept lowering the pressure.
4th – Change the pressure sensor and nothing
5th – Change the main valve box and nothing
6th – Change the main shock absorber ball and nothing
7th – Change the suspension module and “perhaps it was an error, change the configuration of the previous module” and transfer the problem to the new module.
8th – I brought PENTOSIN CHF11S oil from the US and I still have the problem
9º – The car continues to drop the pressure according to my star diagnosis
10º – When I try to do the “automatic leveling” it gives me 180 bar but then the pressure drops I calculate that it is due to the same leveling
The problem that when it is idling (regulating 550 RPM) at a traffic light is alerted and the orange sign appears the suspension stops working, I turn off the engine and turn it back on it works again, if I could increase 100 more rpm it would be solved
My question is, could you enter my star diagnosis remotely and help solve the problem, after payment of course, perhaps it’s just a tune-up that I don’t know how to do
My English is not good so I use a translator to send this email. Thank you very much in advance. I look forward to hearing from you. Regards
Please call our shop at 972-317-4005 to discuss you repairs.