George A.

Have an 2015 S550 RWD with ABC , about 58,000 miles. After starting, and rolling along, about 5 minutes later, I get a warning on the driver's display of "ABC Malfunction". Nothing happens, that I can detect, in the ride or the handling of the car. It happens nearly every time that I drive it.

Occasionally, when I stop for 30 minutes or so, when I drive again, I do not get the display.

Any comments or input from the folks out there that may have had this happen? .I will likely go to my MB Dealer or Independent Service to get their input, but I wanted your inputs first.

Thanks for any help or comments.

Barry Hanna

I don’t have the complete answer, but you need to have a shop pull the codes and see if any come up. You DO NOT want to get yourself into a shut down or limp mode if the system is low on fluid or the pump is having a problem, etc. These are complex systems, a potential problem will not go away and they are very expensive to repair if problems escalate. The system was designed originally to be a lifetime fill, not needing further servicing, however current practice among long-time owners is to change the Petrosin fluid and filter periodically. If it were mine, I’d probably do it every two years or 30,000 miles just to be safe.

We’ve got a few vehicles in the family with ABC systems and no problems so far, but they do regular fluid and filter changes. A Mercedes dealer might not even check the system on a service visit, so don’t leave it to chance.

JohnLane

OP start with verifying fluid level. There is a dipstick on top of the reservoir. The 222 ABC system in your car will use one of two possibilities of fluid. A call to MB with your VIN number will verify which fluid is appropriate. I prefer to check fluid with engine idling; fully warmed up as this mimics how things are as ABC is working.
If you need to add fluid and see no external leaks expect that one of the nitrogen bombs (they look like a bomb from Looney Tunes cartoons) is failing. Most common is the dampener that threads into the ABC pump. When it fails you can’t miss the noise. Easy replacement. You will spend more time cleaning around it with spray brake cleaner to ensure no crud ends up in the pump then removal and replacement.
If this does not solve the issue it is time to plug into XENTRY to see what it thinks of itself.
Fluid needs to be changed every 30,000 or so. I am told that the filter is incorporated into the fluid reservoir for the 222 cars such that a filter replacement is much more involved then in previous cars.

Edit.... Should you find oil all over the reservoir this means one of the nitrogen bombs has failed; the pressurized nitrogen shoved the hydraulic fluid into the reservoir with gas left in the hydraulic lines. Replace nitrogen bomb (ideally all of them), replace all ABC fluid and perform a rodeo to get all the gas out of the system. Not as bad as it sounds.

Barry Hanna

‘Bombs” is the exactly perfect description.

George A.

Thanks, Barry Hanna, for the recommendation. Will take action.

Cheers!

George A.

Thanks to you, JohnLane, for the input. I will combine your and Barry's recommendations, to get the ABC squared away.

Cheers to you, also.

LXXXVIII

hard to say but don't panic you may have a leak somewhere did you check your parking spot?
at 60k miles the reservoir should be ok in my opinion

JohnLane

My car has a front strut that is wet when I change oil. Wipe it off with a shop rag. I got to add fluid to the system about a month before the nitrogen bomb that threads into the pump made ‘that noise.’

George A.

After several inputs, I checked the ABC fluid level, with it's "dipstick". It was about one finger low. I ordered a Liter of Pentosin CHF 11S on Amazon, and added enough to bring it up to the cold fill line. VIOLA! No more messages, no more growling sound when I first start up. Works like it's a new Benz. Thanks again to John Lane and Barry Hanna.