ABC Issues & More

[Marsden]

The purpose of this thread is to collect and organize the best ABC-related intelligence thus far shared in this forum. It's going to be a piecemeal effort at first, and I implore any and all interested parties to make contributions, criticisms, and references wherever indicated.

Originally Posted by Free Advice

Do not buy a W215 CL-Class Mercedes without FIRST familiarizing yourself with the ABC System. This goes treble for old and/or high-mileage examples. Research is a much kinder & gentler teacher than Experience.

For the uninitiated, the ABC (Active Body Control) system is Mercedes's electro-hydraulic suspension which constantly self-monitors and adjusts suspension settings thereby virtually eliminating body roll and pitch in various driving situations including cornering, accelerating, and braking. You'll find it on CL and SL models; however I note that it's been supplanted by Airmatic in the W216 CL.

Originally Posted by MBUSA.COM

Arguably the most advanced suspension system in production, ABC provides an excellent balance of ride comfort and handling while virtually eliminating bodyroll during cornering. A series of sensors and electronically controlled high-pressure hydraulics counteracts the effects of roll, vibration, pitch, dive, and squat. And to help adjust ride quality and responsiveness, the driver can select either Sport or Comfort mode via a button next to the shift knob.

At first, I'm just going to link some of the clearest and most-informative threads I can find (see next post in this thread). Then, later, we'll organize them into the most useful format we can come up with. We've gone too long without having this important information readily accessible. Please contribute your own--just link here to the posts if they're already on the forum, and I'll take care of the cleanup. No way can I do this alone.

Down the road, it may also be useful to have a general-issues sticky for non-ABC matters. (Edit: List begins just below; see next post for ABC Threads.) Like it or not, our cars are aging, they are quite complex, and they'll have issues from time to time. We're here to help each other.

W215 Fuse & Relay Charts

http://www.benzworld.org/forums/w215...lay-chart.html

W215 hidden fuses revealed

http://www.benzworld.org/forums/w215...-revealed.html

2000 Mercedes CL500 Wiring diagram

http://s1089.photobucket.com/albums/...ing%20diagram/

Power assist doors & trunk issues

http://www.benzworld.org/forums/w215...-question.html

Tire advice / consensus

http://www.benzworld.org/forums/w215...est-tires.html

Before starting a new thread:

[Marsden]

These ABC Threads are not collected here because every post within them is gold. They're just a basic step in organizing the information. Comments (and contributions) are more than welcome.

Active Body Control - Recall, Filters, Fluid

Can you just remove the ABC System?

ABC Problems - Alternate "Solutions"

Possible ABC Preventative Solution?

Recurring Problems with ABC

ABC Light warning question

Arnott ABC Conversion Kit

ABC system in CL cars

Should I buy a CL?

ABC Reliability

ABC Diagrams

ABC Warning Light

ABC Fluid Maintenance

ABC Filter Upgrade & Fluid Check VIDEO

ABC Warning Over Bumps - Accumulators?

Recall for ABC problem means free fix or no?

ABC Valve Block Repair / Rebuild (see next thread)

W215 ABC Pump/Valve Block/HPE Hose Repair (21 Pictures)

So what EXACTLY about the ABC prevents it from being removed?

HELP! Found wheel sitting in the wheel well after 3 days of no driving

Official MB Service Bulletin re: "Vehicle Level Lowers After Being Parked"

[Zia Mirza]

I am a new comer to this forrum and appreciate the tremendous amount information on this site. I own a 2000 CL500 (my 5th mercedes).
Last week a humming noise started coming, took it to my independent service guy, the hydraulic oil was real low. He also checked the transmission and power steering oil as well. The noise is still coming at low RPM only.
The suspension works fine, level ajdustment is fine and there is no ABC light.
I have three questions from the experts:
A. Is it ABC pulsation Damper/accumulator which is causing this humming noise?
B. one of the on-line auto part store listed two different accumulators e.g. (1) Center suspension accumulator return air suspension (P/N 220-320-0415-OR) $170 the other, (2) Front suspension accumulator (P/N 220-327-0215LEMF) $123. Which of the accumulator do I need to order?
C. The schematics diagram given on this site is not very clear. Is there an explanation to where this accumulator is located and how to get to it? and is there any precuations, bleeding etc is needed?
Thanks in advance
"Life is just like Jazz, it's best when you improvise"

[calgary]

Humming noise - might be a problem developing with the AC compressor - That is what happended to my CL500.....

[Zia Mirza]

Thanks for the resoponse
The noise persist with or without AC

[ifari]

(P/N 220-327-0215 air reservoir) is the part you need. It is found under the car towards the front center slightly closer to the passenger side.
Lift on a hoist.
Let the car suspension settle for 5 minutes before removing the old Dampner. It is advised to bleed off the suspension, but my tech didn't do it.
It is a simple wrench off/on job and should take less than 10 minutes.
Remember to top up the ABC fluid afterwards as you will have a ruptured Dampner and it will have had some fluid trapped within.
Have the dealership do it for you and it will probably be no more than 1 hr. labour after they have inspected the lines first and then changed the Accumulator/Dampner.
Good luck and let us know how things work out.

[Zia Mirza]

Thanks Bob for your timely response.
I ordered the part you recommended and an extra quart of hydraulic oil.
I do not have a hoist, would raise the car on hydraulic jack and back-up stand and will try to work on it.
Hopefully I will not spill too much oil when I repace the accumulator
Will report on the results when the job is successfully finished

"Remember to work like you don't need the money, dance like nobody's watching, and love like you've never ever been hurt"

[ifari]

No problem...you are welcome.

[Zia Mirza]

Thanks a million to all the members for their response, particularly Bob who identified the accumualator P/N.
This afternoon I replaced the damper/accumulator and indeed it was very easy (I just had to buy a 15/16" wrench). The noise went away and the engine sounds like brand new.
Happy ending and saved lots of $$, learned a few new things and of course the satisfaction and sense of acheivement was in valuable

[ifari]

Originally Posted by Zia Mirza

Thanks a million to all the members for their response, particularly Bob who identified the accumualator P/N.
This afternoon I replaced the damper/accumulator and indeed it was very easy (I just had to buy a 15/16" wrench). The noise went away and the engine sounds like brand new.
Happy ending and saved lots of $$, learned a few new things and of course the satisfaction and sense of acheivement was in valuable

That's great. Congratulations!

.... the quote is by reggae superstar and Rastaman, Bob Marley, of Bob Marley and The Wailers.

YouTube - Bob Marley & The Wailers - Trenchtown rock (Live)

YouTube - Bob Marley & The Wailers - Trenchtown rock (Live)

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