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1988 BMW M5, 1989 BMW M3, 1979 Mercedes 450 SEL 6.9, 2006 SL55 AMG w/ P30 Performance Pack
Strange Behavior Of ABC System - Fixed
Hello,
I just wanted to give a heads up for everyone who may have issues with their ABC troubleshooting. As you know I replaced my entire system (After selling my eldest child ) over a year ago. The other day, the car did a rodeo test after accelerating briskly due to a pesky BMW M3. It's scary when you are driving and all of sudden you think the freeway overpass you're on is swaying in the wind. The car threw the dreaded red ABC - Drive Carefully message on the dash. Both rear axles automatically went to their highest position and stayed that way for two days. Having all new components, a failure seemed impossible but, less we forget those tiny little electrical parts that can shut down the whole system.
My buddy came over with his STAR and found the right front acceleration sensor was bad! (Part # 004 542 35 18 280) Replace it for $59.00 at my local wholesale parts store and all is good. I know I have had some members show this behavior and I have not seen anyone recommending checking the two front sensors location at each shock tower for failures. I even reviewed some of the very good and detailed troubleshooting post from years past and no mention of speed sensors being a possible culprit. I think there may be two or one more for the rear. Of course you will need a STAR to determine a sensor is bad. And with these newer cars you can put away your OHM meters because the STAR gives you all values! It's a good idea to change these sensors as added piece of mind since they are relatively cheap. Hope this helps to troubleshoot any weird behaviour from your ABC.
No reason to change them unless they are bad, but yes, if they fail the car will default to high so it stays drivable. I had one acting up on my car, did a couple rodeo cycles, performed the teach-in calibration for the sensors (car goes from max height to the floor almost instantly lol), and it has been good ever since. The very early cars had a bulletin about replacing them to the newest part # but it hasn't changed in a decade.
No reason to change them unless they are bad, but yes, if they fail the car will default to high so it stays drivable. I had one acting up on my car, did a couple rodeo cycles, performed the teach-in calibration for the sensors (car goes from max height to the floor almost instantly lol), and it has been good ever since. The very early cars had a bulletin about replacing them to the newest part # but it hasn't changed in a decade.
I have something similar but not quite the same.... My 2009 SL550 (about the same time as putting 295 michelins on as they didnt have 285s) has a weird issue where the rear end "rocks" as if each side is fighting each other only under heavy acceleration.
I can not give more than 2/3 pedal or it will do this and I have to let off just to "stabilize" ... any ideas?
Is that ABC action, or are you losing traction? A combination of the design of the differential and the ESP system will cause the rear end to wiggle like that as the tires seek traction on hard acceleration. With worn tires, I can even cause that at speeds if I hammer it.
1988 BMW M5, 1989 BMW M3, 1979 Mercedes 450 SEL 6.9, 2006 SL55 AMG w/ P30 Performance Pack
Originally Posted by ItalianJoe1
No reason to change them unless they are bad, but yes, if they fail the car will default to high so it stays drivable. I had one acting up on my car, did a couple rodeo cycles, performed the teach-in calibration for the sensors (car goes from max height to the floor almost instantly lol), and it has been good ever since. The very early cars had a bulletin about replacing them to the newest part # but it hasn't changed in a decade.
Yes. The elevation change is fast and almost violent in nature. I have a door open and it almost hit my car parked next to her. 😜
1988 BMW M5, 1989 BMW M3, 1979 Mercedes 450 SEL 6.9, 2006 SL55 AMG w/ P30 Performance Pack
ABC
Originally Posted by Rudeney
Is that ABC action, or are you losing traction? A combination of the design of the differential and the ESP system will cause the rear end to wiggle like that as the tires seek traction on hard acceleration. With worn tires, I can even cause that at speeds if I hammer it.
Sorry, I should have clarified. The rodeo was cycling while doing 70 mph on the freeway makes it feel like your losing traction but it’s not. (All 4 sides lower and raise alternately) I really think it’s dangerous for the car to do a rodeo cycle at any speed but I guess that’s something I can’t control.
Is that ABC action, or are you losing traction? A combination of the design of the differential and the ESP system will cause the rear end to wiggle like that as the tires seek traction on hard acceleration. With worn tires, I can even cause that at speeds if I hammer it.
I am not losing traction as the tires are brand new pilot super sports.... i barely can get them to spin if I wanted! .....
Also, it happens at any speed even say 55 mph to 90 mph...
I have something similar but not quite the same.... My 2009 SL550 (about the same time as putting 295 michelins on as they didnt have 285s) has a weird issue where the rear end "rocks" as if each side is fighting each other only under heavy acceleration.
I can not give more than 2/3 pedal or it will do this and I have to let off just to "stabilize" ... any ideas?
I had a similar issue, and it was a slow leak from a rear tire. Check the tire pressures all around to make sure they match.
Also, it happens at any speed even say 55 mph to 90 mph...
It would seem either an errant sensor is causing the ABC controller to respond inappropriately, 'rum, or your ABC controller is faulty.
I presume you can reproduce the suspension anomaly reliably. If that's the case, then I would use Star Diagnosis to monitor the voltages of all ABC sensor inputs and see if one initiates the anomaly. For this the engineering menus are indispensible, though they are auf Deutsch. They allow you to select sensor voltages to be charted in real time.
I am submitting the engineering menus as Exhibit D as to why it's worth paying-up for Star Diagnosis over the iCarsoft products.
I just swapped out my front sensor that tested fine in DAS but kept throwing a red ABC light. I swapped it with an equally old sensor to see if this solves the problem.
Which sensor are you referring to and why do you think it was responsible for you red ABC light? I don't believe that there is any teach-in or calibration on acceleration sensors, there is calibration on level sensors but you should be pretty close with just a plug and play replacement.
Which sensor are you referring to and why do you think it was responsible for you red ABC light? I don't believe that there is any teach-in or calibration on acceleration sensors, there is calibration on level sensors but you should be pretty close with just a plug and play replacement.
The mercedes computer told me "error in this sensor" and then I swapped it out and the error went away. It's the acceleration sensor for the front left (also part of the ESP).
Good, it sounded like DAS was showing that the sensor was good, so I was wondering why you replaced it. You can also see all of the 5 acceleration sensor values in DAS, all should be very close to 2500mA with the car stationary.
Good, it sounded like DAS was showing that the sensor was good, so I was wondering why you replaced it. You can also see all of the 5 acceleration sensor values in DAS, all should be very close to 2500mA with the car stationary.
It was giving an intermittent fault that went away with replacement.
02-13-2019, 04:52 PM
) over a year ago. The other day, the car did a rodeo test after accelerating briskly due to a pesky BMW M3. It's scary when you are driving and all of sudden you think the freeway overpass you're on is swaying in the wind. The car threw the dreaded red ABC - Drive Carefully message on the dash. Both rear axles automatically went to their highest position and stayed that way for two days. Having all new components, a failure seemed impossible but, less we forget those tiny little electrical parts that can shut down the whole system.
It's a good idea to change these sensors as added piece of mind since they are relatively cheap. Hope this helps to troubleshoot any weird behaviour from your ABC.
